Septic systems as sources of organic wastewater compounds in domestic drinking water wells in a shallow sand and gravel aquifer

May combine two claims.

The two wells with the highest boron concentrations (250 and 91 μg/L) also had two of the three highest nitrate concentrations (≥5 mg/L), consistent with septic systems as the main source.

“The two wells with the highest [B] (250 and 91 μg/L) also had two of the three highest [NO 3 -] (≥5 mg/L), consistent with septic systems as the main source.”

May combine two claims.

The four wells with non-detectable nitrate had ≤13 μg/L boron, consistent with background concentrations in Cape Cod groundwater (~10 μg/L).

“The four wells with non-detectable NO 3 -had ≤13 μg/L B, consistent with background concentrations in Cape Cod groundwater (~10 μg/L B; Schaider et al., 2014).”

• cites Schaider et al., 2014 sourceNot checked yet

  Not checked in the free run.

May combine two claims.

Among the 20 wells tested, nitrate concentrations varied by more than a factor of 100, and total nitrogen and boron concentrations ranged by more than a factor of 25.

“Among the 20 wells that we tested for OWCs, concentrations of nitrate (NO 3 -) varied by more than a factor of 100, and total nitrogen (TN) and boron (B) concentrations ranged by more than a factor of 25 (Table 1).”

May combine two claims.

Five wells had nitrate consistent with background or minimal anthropogenic impact (<0.5 mg/L), five showed moderate impact (0.5-2.5 mg/L), and 10 were highly impacted (>2.5 mg/L).

“Five wells had [NO 3 -] consistent with background or minimal anthropogenic impact (b0.5 mg/L), five wells showed moderate impact (0.5-2.5 mg/L), and 10 were highly impacted (N 2.5 mg/L).”

The quote only partly states this claim.

Boron concentrations in the 20 wells ranged from 6.3 to 250 μg/L.

“Boron (B) concentrations ranged from 6.3 to 250 μg/L.”

May combine two claims.

Nitrate, boron, and well depth were all correlated with PFASs and pharmaceuticals in the 20 domestic wells tested.

“Nitrate, boron, and well depth were all correlated with PFASs and pharmaceuticals.”

May combine two claims.

Chlorinated organophosphate flame retardants, including three detected in public wells on Cape Cod (TCEP, TDCPP, TCPP), were not detected, even though they tend to be more resistant to biodegradation than non-halogenated OPFRs.

“We did not detect chlorinated OPFRs, including three that we detected in public wells on Cape Cod (TCEP, TDCPP, TCPP; Schaider et al., 2014), even though they tend to be more resistant to biodegradation than non-halogenated OPFRs (Meyer and Bester, 2004).”

• cites Schaider et al., 2014 sourceNot checked yet

  Not checked in the free run.

• cites Meyer and Bester, 2004Not checked yet

  Not checked in the free run.

May combine two claims.

Simvastatin was detected in one well (14 ng/L), the first reported detection in drinking water.

“Simvastatin was detected in one well (14 ng/L), the first reported detection in drinking water.”

May combine two claims.

PFBS and PFHxS had the strongest correlation and most linear relationship, suggesting a common source, although temporal trends in production of these PFASs vary.

“PFBS and PFHxS had the strongest correlation and most linear relationship, suggesting a common source, although temporal trends in production of these PFASs vary.”

May combine two claims.

Nine pharmaceuticals were detected in only one or two wells, consistent with a high degree of heterogeneity in groundwater pharmaceutical concentrations.

“Nine pharmaceuticals were detected in only one or two wells, consistent with a high degree of heterogeneity in groundwater pharmaceutical concentrations.”

May combine two claims.

Nonylphenol, octylphenol, NP ethoxycarboxylates, and NP ethoxylates were not detected in the current study.

“We did not detect nonylphenol (NP), octylphenol (OP), NP ethoxycarboxylates (NPECs), or NP ethoxylates (NPEOs) in the current study.”

May combine two claims.

PFNA (<0.45 ng/L) and PFDA (<0.28 ng/L) were not detected in any of the samples tested on Cape Cod.

“We did not detect PFNA (b0.45 ng/L) or PFDA (b 0.28 ng/L) in any of the samples tested on Cape Cod.”

May combine two claims.

Seventy-seven percent of organic wastewater compounds were not detected in any sample, including all tested alkylphenols and herbicides.

“Seventy-seven percent of OWCs were not detected in any sample, including all tested alkylphenols and herbicides.”

May combine two claims.

Twelve pharmaceuticals, including five antibiotics, were detected out of 59 pharmaceutical analytes, and 13 wells (65%) had detectable concentrations of at least one pharmaceutical.

“We detected twelve pharmaceuticals, including five antibiotics, out of a total of 59 pharmaceutical analytes, and 13 wells (65%) had detectable concentrations of at least one pharmaceutical.”

May combine two claims.

The maximum concentrations of PFHxS and PFBS on Cape Cod were generally higher than those reported in five other studies of PFASs in raw drinking water and were within a factor of two of the maximum concentrations reported in these studies.

“The maximum concentrations of two perfluoroalkane sulfonates, PFHxS and PFBS, on Cape Cod were generally higher than those reported in the other studies and were within a factor of two of the maximum concentrations reported in these studies (Table 2).”

May combine two claims.

While PFOA concentrations in most wells were ≤4 ng/L, five wells had PFOA concentrations of 2-3 ng/L after subtracting the field blank concentration; these five wells were among the six with detectable concentrations of five other PFASs.

“While PFOA concentrations in most wells were ≤4 ng/L, five wells had PFOA concentrations of 2-3 ng/L after subtracting the field blank concentration; these five wells were among the six with detectable concentrations of five other PFASs.”

May combine two claims.

The two most frequently detected pharmaceuticals, which also had the highest maximum concentrations, were sulfamethoxazole (9 wells above 0.1 ng/L; maximum 60 ng/L) and carbamazepine (5 wells above 0.07 ng/L; maximum 62 ng/L).

“The two most frequently detected pharmaceuticals, which also had the highest maximum concentrations, were sulfamethoxazole (9 wells above 0.1 ng/L; maximum 60 ng/L) and carbamazepine (5 wells above 0.07 ng/L; maximum 62 ng/L).”

May combine two claims.

Four PFASs (PFOS, PFHxS, PFBS, and PFHxA) were detected in ≥50% of wells tested, and another (PFHpA) was detected in 30% of wells.

“Four PFASs (PFOS, PFHxS, PFBS, and PFHxA) were detected in ≥50% of wells we tested, and another (PFHpA) was detected in 30% of wells.”

May combine two claims.

The maximum sulfamethoxazole concentration in this study matched or exceeded the maximum concentration in five drinking water studies and was within a factor of 3 of the maximum concentration in five other studies.

“The maximum sulfamethoxazole concentration in this study matched or exceeded the maximum concentration in five drinking water studies (Zimmerman, 2005;Stackelberg et al., 2007;Focazio et al., 2008;Illinois EPA, 2008;Tabe, 2010), and was within a factor of 3 of the maximum concentration in five other studies (Verstraeten et al., 2005;Benotti et al., 2009;Fram and Belitz, 2011;Erickson et al., 2014;”

• cites Zimmerman, 2005Not checked yet

  Not checked in the free run.

• cites Stackelberg et al., 2007 sourceNot checked yet

  Not checked in the free run.

• cites Focazio et al., 2008 sourceNot checked yet

  Not checked in the free run.

May combine two claims.

Acesulfame was the most frequently detected organic wastewater compound, found in 17 wells (85%).

“Acesulfame (or Ace K), an artificial sweetener, was the most frequently detected OWC, found in 17 wells (85%).”

May combine two claims.

Seventeen wells (85%) contained detectable concentrations of at least one organic wastewater compound, with a maximum of 13 compounds detected in a single well.

“Seventeen wells (85%) contained detectable concentrations of at least one OWC, with a maximum of 13 OWCs detected in a single well.”

May combine two claims.

Among the nine hormone target analytes, only two were detected (progesterone and cis-testosterone), at relatively low concentrations (0.02-0.04 ng/L), in a total of four wells (20%).

“Among the nine hormone target analytes, only two were detected (progesterone and cis-testosterone), at relatively low concentrations (0.02-0.04 ng/L), in a total of four wells (20%).”

May combine two claims.

Six wells had detectable concentrations of all five of these PFASs, and one well had the highest concentrations of PFHxS (41 ng/L), PFBS (23 ng/L), and PFHxA (2 ng/L).

“Six wells had detectable concentrations of all five of these PFASs, and one well had the highest concentrations of PFHxS (41 ng/L), PFBS (23 ng/L), and PFHxA (2 ng/L).”

May combine two claims.

Compared to wells >15 m in depth, wells <15 m had higher median N detects (8 vs. 4 compounds), Σ[pharma] (5.0 vs. 0.4 ng/L) and Σ[PFAS] (6.0 vs. 0.5 ng/L).

“Compared to wells N15 m in depth, wells b15 m had higher median N detects (8 vs. 4 compounds), Σ[pharma] (5.0 vs. 0.4 ng/L) and Σ[PFAS] (6.0 vs. 0.5 ng/L).”

May combine two claims.

Compared to wells with <1 mg/L nitrate, wells with >1 mg/L nitrate had three times as many detectable organic wastewater compounds, 6.2 times higher Σ[PFAS] and higher Σ[pharma] (2 vs. 0 ng/L).

“Compared to wells with b1 mg/L NO 3 , wells with N 1 mg/L NO 3 had three times as many detectable OWCs, 6.2 times higher Σ[PFAS] and higher Σ[pharma] (2 vs. 0 ng/L).”

May combine two claims.

Wells with >20 μg/L boron had 3.8 times more detectable organic wastewater compounds, 7.4 times higher Σ[PFAS], and 8.8 times higher Σ[pharma] than wells with 10-20 μg/L boron.

“Wells with N 20 μg/L B had 3.8 times more detectable OWCs, 7.4 times higher Σ[PFAS], and 8.8 times higher Σ[pharma] than wells with 10-20 μg/L B (Fig. 3).”

May combine two claims.

The well with the second highest nitrate concentration (8 mg/L) had 21 μg/L boron (just below the median) and ~0.4 ng/L acesulfame (lowest detected concentration), and no other detected organic wastewater compounds, suggesting that the relatively high nitrate came from another source.

“For instance, the well with second highest [NO 3 -] (8 mg/L) had 21 μg/L [B] (just below the median) and ~0.4 ng/L acesulfame (lowest detected concentration), and no other detected OWCs, suggesting that the relatively high [NO 3 -] came from another source.”

May combine two claims.

Wells with total organic carbon >1 mg/L had higher median N detects (10 vs. 5 compounds), Σ[pharma] (7 vs. 0.4 ng/L), and Σ[PFAS] (11 vs. 0.8 ng/L) compared to wells with total organic carbon <1 mg/L.

“Wells with TOC N 1 mg/L had higher median N detects (10 vs. 5 compounds), Σ[pharma] (7 vs. 0.4 ng/L), and Σ[PFAS] (11 vs. 0.8 ng/L) compared to wells with TOC b 1 mg/L.”

May combine two claims.

Some wells, particularly those in close proximity to the coastline, may have derived some of their boron from seawater intrusion or coastal flooding; concentrations of boron and sodium were correlated (ρ = 0.68, p < 0.001).

“Some wells, particularly those in close proximity to the coastline, may have derived some of their B from seawater intrusion or coastal flooding ([B] in seawater: ~4.4 mg/L); concentrations of B and sodium (Na) were correlated (ρ = 0.68, p b 0.001).”

May combine two claims.

Well W09 had the highest acesulfame concentration (5300 ng/L) and the highest concentration of three PFASs (PFHxS, PFBS, PFHxA).

“This well had the highest acesulfame concentration (5300 ng/L) and the highest concentration of three PFASs (PFHxS, PFBS, PFHxA).”

Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

Well W09 was located 3.2 km from a capped landfill, although the well was not directly downgradient of the landfill.

“One of these two wells, W09, was located 3.2 km from a capped landfill, although the well was not directly downgradient of the landfill.”

May combine two claims.

Well W03 had elevated Σ[PFAS] (26 ng/L) and relatively low [NO3-] (0.8 mg/L) and did not appear to be located downgradient of a landfill.

“Another well (W03) with elevated Σ[PFAS] (26 ng/L) and relatively low [NO 3 -] (0.8 mg/L) did not appear to be located downgradient of a landfill.”

May combine two claims.

The presence of OWCs was correlated with concentrations of nitrate, boron, and acesulfame (artificial sweetener), and inversely correlated with well depth.

“The presence of OWCs was correlated with concentrations of nitrate, boron, and acesulfame (artificial sweetener), and inversely correlated with well depth.”

Classified as probably not a substantial claim.

Coliform bacteria counts and nitrate and phosphate concentrations were higher in domestic wells closer to septic tanks in Florida.

“Coliform bacteria counts and nitrate and phosphate concentrations were higher in domestic wells closer to septic tanks in Florida (Arnade, 1999)”

• cites Arnade, 1999 sourceNot checked yet

  Not checked in the free run.

Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

Among 3465 domestic wells tested throughout the US, 90% had >0.01 mg/L nitrate, 8% had >10 mg/L nitrate, and the mean concentration was 3.6 mg/L.

“Among 3465 domestic wells tested throughout the US (Focazio et al., 2006), 90% had N0.01 mg/L NO 3 -(compared with 80% in our study), 8% had N 10 mg/L NO 3 -(compared with 5% in our study), and the mean concentration was 3.6 mg/L (compared with 2.9 mg/L in our study).”

• cites Focazio et al., 2006 sourceNot checked yet

  Not checked in the free run.

Probably not a substantial claim: may not pass S3 (load-bearing).

In a sampling of over 3800 domestic wells in Wisconsin, USA, 47% exceeded at least one health guideline for nitrate, coliform bacteria, fluoride, or metals.

“In a sampling of over 3800 domestic wells in Wisconsin, USA, 47% exceeded at least one health guideline for nitrate, coliform bacteria, fluoride, or metals (Knobeloch et al., 2013)”

• cites Knobeloch et al., 2013Not checked yet

  Not checked in the free run.

May combine two claims.

In Nebraska wells ≤15 m from septic systems, concentrations of ammonium exceeded those of nitrate, indicating reducing conditions.

“In Nebraska wells ≤ 15 m from septic systems, concentrations of NH 4 + exceeded those of NO 3 -, indicating reducing conditions.”

• cites Verstraeten et al., 2005 sourceNot checked yet

  Not checked in the free run.

Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

A compilation of domestic well testing throughout the US showed exceedances of drinking water standards in 8.4% of wells for nitrate and 11% of wells for arsenic.

“a compilation of domestic well testing throughout the US showed exceedances of drinking water standards in 8.4% of wells for nitrate and 11% of wells for arsenic (Focazio et al., 2006)”

• cites Focazio et al., 2006 sourceNot checked yet

  Not checked in the free run.

Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

In a study of 26 shallow wells in Nebraska, USA, the median nitrate concentration was <0.05 mg/L and the maximum was 39 mg/L.

“in a study of 26 shallow wells in Nebraska, USA, the median [NO 3 -] was b 0.05 mg/L and the maximum was 39 mg/L (Verstraeten et al., 2005).”

• cites Verstraeten et al., 2005 sourceNot checked yet

  Not checked in the free run.

May combine two claims.

Septic systems are likely the main source of organic wastewater compounds in the domestic wells tested, though landfills may also affect some wells.

“Septic systems are likely the main source; landfills may also affect some wells.”

May combine two claims.

The high proportion of nitrate in total nitrogen indicates oxic conditions in all groundwater samples and minimal contributions from ammonia, organic nitrogen, or other nitrogen species.

“an indication of oxic conditions in all groundwater samples and minimal contributions from ammonia (NH 4 + ), organic N, or other N species.”

Probably not a substantial claim: may not pass S3 (load-bearing).

Diarrheal disease in children was associated with density of nearby septic systems in Wisconsin.

“diarrheal disease in children was associated with density of nearby septic systems in Wisconsin (Borchardt et al., 2003).”

• cites Borchardt et al., 2003 sourceNot checked yet

  Not checked in the free run.

Probably not a substantial claim: may not pass S3 (load-bearing).

Verstraeten et al. (2005) detected 14 pharmaceuticals in domestic wells in a shallow sand and gravel aquifer in central US.

“Verstraeten et al. (2005) detected 14 pharmaceuticals in domestic wells in a shallow sand and gravel aquifer in central US”

• cites Verstraeten et al., 2005 sourceNot checked yet

  Not checked in the free run.

Probably not a substantial claim: may not pass S3 (load-bearing).

Erickson et al. (2014) detected several pharmaceuticals in domestic wells in both glacial and bedrock aquifers.

“Erickson et al. (2014) detected several pharmaceuticals in domestic wells in both glacial and bedrock aquifers.”

• cites Erickson et al., 2014Not checked yet

  Not checked in the free run.

May combine two claims.

The distribution of nitrate in this study was similar to that of Focazio et al.'s broader nationwide study, although their sampling was not part of a nationally representative sampling design.

“This comparison suggests that the distribution of [NO 3 -] in our study was similar to that of Focazio et al.'s broader nationwide study, although their sampling was not part of a nationally representative sampling design.”

• cites Focazio et al., 2006 sourceNot checked yet

  Not checked in the free run.

Probably not a substantial claim: may not pass S3 (load-bearing).

The range of well depths was similar in both studies (5-30 m in Nebraska, 3-40 m on Cape Cod).

“The range of well depths was similar in both studies (5- 30 m in Nebraska, 3-40 m on Cape Cod).”

• cites Verstraeten et al., 2005 sourceNot checked yet

  Not checked in the free run.

Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

Production of PFOS, PFHxS, and PFOA has declined in the US since the early 2000s following a phase-out of POSF-related chemicals by 3M and subsequent stewardship plans by US EPA, and this has resulted in declines in blood serum concentrations of these three PFASs in Americans.

“Production of PFOS, PFHxS, and PFOA has declined in the US since the early 2000s following a phase-out of POSF-related chemicals by 3M and subsequent stewardship plans by US EPA, and this has resulted in declines in blood serum concentrations of these three PFASs in Americans (Calafat et al., 2007;Olsen et al., 2008).”

• cites Calafat et al., 2007 sourceNot checked yet

  Not checked in the free run.

• cites Olsen et al., 2008 sourceNot checked yet

  Not checked in the free run.

May combine two claims.

Although the authors previously found three endogenous hormones in groundwater-fed ponds on Cape Cod (3-6.5 ng/L), they did not detect hormones in 20 public wells on Cape Cod (MRLs 0.1-0.5 ng/L).

“Although we previously found three endogenous hormones in groundwater-fed ponds on Cape Cod (3-6.5 ng/L; Standley et al., 2008), we did not detect hormones in 20 public wells on Cape Cod (MRLs 0.1-0.5 ng/L; Schaider et al., 2014).”

• cites Standley et al., 2008 sourceNot checked yet

  Not checked in the free run.

• cites Schaider et al., 2014 sourceNot checked yet

  Not checked in the free run.

May combine two claims.

As domestic wells have much smaller recharge areas than public supply wells, the presence of prescription medications depended on whether the well pulled from an area where a resident was using that medication and the persistence of the compound in groundwater.

“As domestic wells have much smaller recharge areas than public supply wells, the presence of prescription medications depended on whether the well pulled from an area where a resident was using that medication and the persistence of the compound in groundwater.”

Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

While PFNA and PFDA are often less frequently detected than shorter-chain PFASs, maximum concentrations of PFNA (96 ng/L) and PFDA (3.3 ng/L) were much higher in other studies.

“While these two longer chain carboxylates are often less frequently detected than shorter-chain PFASs, maximum concentrations of PFNA (96 ng/L; Post et al., 2013) and PFDA (3.3 ng/L: Quiñones and Snyder, 2009) were much higher in other studies.”

• cites Post et al., 2013 sourceNot checked yet

  Not checked in the free run.

• cites Quiñones and Snyder, 2009Not checked yet

  Not checked in the free run.

Probably not a substantial claim: may not pass S3 (load-bearing).

Sulfamethoxazole and carbamazepine have been among the most frequently detected organic wastewater compounds in drinking water and groundwater.

“Sulfamethoxazole and carbamazepine have been among the most frequently detected OWCs in drinking water and groundwater (Barnes et al., 2008;Benotti et al., 2009;Erickson et al., 2014;Schaider et al., 2014).”

• cites Barnes et al., 2008 sourceNot checked yet

  Not checked in the free run.

• cites Benotti et al., 2009 sourceNot checked yet

  Not checked in the free run.

• cites Erickson et al., 2014Not checked yet

  Not checked in the free run.

Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

PFBS is used as a replacement for POSF-related chemicals (e.g., PFOS and PFHxS) and PFHxA is used as a shorter-chain analog of PFOA.

“By contrast, PFBS is used as a replacement for POSF-related chemicals (e.g., PFOS and PFHxS) and PFHxA is used as a shorter-chain analog of PFOA (Wang et al., 2013).”

• cites Wang et al., 2013 sourceNot checked yet

  Not checked in the free run.

Probably not a substantial claim: may not pass S3 (load-bearing).

Phillips et al. (2015) reported 20 μg/L TBEP in groundwater downgradient of a septic system serving an elder care facility where the most likely source was floor wax.

“Phillips et al. (2015) reported 20 μg/L TBEP in groundwater downgradient of a septic system serving an elder care facility where the most likely source was floor wax.”

• cites Phillips et al., 2015 sourceNot checked yet

  Not checked in the free run.

May combine two claims.

Aerobic sand filters in onsite wastewater treatment systems were shown to remove >90% of steroid estrogens and mass loss of 17β-estradiol was observed in a wastewater treatment plant plume on Cape Cod.

“Aerobic sand filters in onsite wastewater treatment systems were shown to remove N 90% of steroid estrogens (Stanford and Weinberg, 2010) and mass loss of 17βestradiol was observed in a wastewater treatment plant plume on Cape Cod (Barber et al., 2009).”

• cites Stanford and Weinberg, 2010Not checked yet

  Not checked in the free run.

• cites Barber et al., 2009 sourceNot checked yet

  Not checked in the free run.

May combine two claims.

The presence of reducing conditions in the Nebraska aquifer likely promoted greater persistence of pharmaceuticals and other organic wastewater compounds, whereas oxic conditions in the Cape Cod aquifer promoted greater microbial degradation.

“Thus the presence of reducing conditions in the Nebraska aquifer likely promoted greater persistence of pharmaceuticals and other OWCs, whereas oxic conditions in the Cape Cod aquifer promoted greater microbial degradation.”

May combine two claims.

Several organic wastewater compounds detected in the Nebraska wells but not in the Cape Cod wells (acetaminophen, caffeine, paraxanthine) are well-removed in septic system leach fields and typically only persist in anoxic groundwater.

“Several OWCs detected in the Nebraska wells but not in the Cape Cod wells (acetaminophen, caffeine, paraxanthine) are well-removed in septic system leach fields (Wilcox et al., 2009;Katz et al., 2010) and typically only persist in anoxic groundwater (Swartz et al., 2006).”

• cites Wilcox et al., 2009 sourceNot checked yet

  Not checked in the free run.

• cites Katz et al., 2010 sourceNot checked yet

  Not checked in the free run.

• cites Swartz et al., 2006 sourceNot checked yet

  Not checked in the free run.

May combine two claims.

Simvastatin was not detected in 20 public wells on Cape Cod (<5 ng/L), in 19 US drinking water sources (<1 ng/L), or in 5 drinking water sources in Illinois (<1 ng/L).

“It was not detected in 20 public wells on Cape Cod (b5 ng/L, Schaider et al., 2014), in 19 US drinking water sources (b 1 ng/L, Benotti et al., 2009), or in 5 drinking water sources in Illinois (b1 ng/L, Illinois EPA, 2008).”

• cites Schaider et al., 2014 sourceNot checked yet

  Not checked in the free run.

• cites Benotti et al., 2009 sourceNot checked yet

  Not checked in the free run.

• cites Illinois EPA, 2008Not checked yet

  Not checked in the free run.

Probably not a substantial claim: may not pass S3 (load-bearing).

The low detection frequencies for organophosphate flame retardants in Cape Cod wells may reflect relatively low concentrations in domestic wastewater compared to wastewater in other locations with greater industrial, commercial, or institutional inputs.

“The low detection frequencies for OPFRs in Cape Cod wells may reflect relatively low concentrations in domestic wastewater compared to wastewater in other locations with greater industrial, commercial, or institutional inputs.”

Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

The relatively high concentrations in the Nebraska wells may be due to closer proximity between wells and septic systems or to older, less effective onsite treatment systems.

“The relatively high concentrations in the Nebraska wells may be due to closer proximity between wells and septic systems or to older, less effective onsite treatment systems.”

Classified as probably not a substantial claim. May combine two claims.

NP, NPEOs, and NPECs were persistent in anoxic groundwater in a plume from a septic system leach pit but were not detected in oxic groundwater within the same plume.

“NP, NPEOs, and NPECs were persistent in anoxic groundwater in a plume from a septic system leach pit but were not detected in oxic groundwater within the same plume (Swartz et al., 2006).”

• cites Swartz et al., 2006 sourceNot checked yet

  Not checked in the free run.

Probably not a substantial claim: may not pass S3 (load-bearing).

Shallower wells have previously been found to show the greatest impact from septic systems and other pollution sources.

“Shallower wells have previously been found to show the greatest impact from septic systems and other pollution sources.”

May combine two claims.

In a survey of organic wastewater compounds in 47 US wells suspected to be impacted by septic systems, landfills, animal feedlots, and other contamination sources, well depth was negatively correlated with N detects, and the median N detects was more than twice as high in shallow wells (<10 m) compared to deeper wells (>50 m).

“In a survey of OWCs in 47 US wells suspected to be impacted by septic systems, landfills, animal feedlots, and other contamination sources (Barnes et al., 2008), well depth was negatively correlated with N detects , and the median N detects was more than twice as high in shallow wells (b10 m) compared to deeper wells (N50 m).”

• cites Barnes et al., 2008 sourceNot checked yet

  Not checked in the free run.

Probably not a substantial claim: may not pass S3 (load-bearing).

Among 29 domestic wells in Minnesota, USA, deeper bedrock wells (33-87 m) tended to have higher concentrations of sulfamethoxazole and carbamazepine than shallower wells (9-34 m) in a glacial sand and gravel aquifer.

“Among 29 domestic wells in Minnesota, USA, deeper bedrock wells (33-87 m) tended to have higher concentrations of sulfamethoxazole and carbamazepine than shallower wells (9-34 m) in a glacial sand and gravel aquifer (Erickson et al., 2014).”

• cites Erickson et al., 2014Not checked yet

  Not checked in the free run.

May combine two claims.

In general, shallower wells pull younger groundwater more recently in contact with the atmosphere with shorter flow paths that allow less time for sorption and biodegradation processes.

“In general, shallower wells pull younger groundwater more recently in contact with the atmosphere (Plummer and Friedman, 1999) with shorter flow paths that allow less time for sorption and biodegradation processes.”

• cites Plummer and Friedman, 1999Not checked yet

  Not checked in the free run.

Probably not a substantial claim: may not pass S3 (load-bearing).

In some shallow groundwater systems close to septic system discharges where reducing conditions predominate, the majority of total nitrogen can be present as ammonium.

“In some shallow groundwater systems close to septic system discharges where reducing conditions predominate, the majority of TN can be present as NH 4 + (Verstraeten et al., 2005;Swartz et al., 2006).”

• cites Verstraeten et al., 2005 sourceNot checked yet

  Not checked in the free run.

• cites Swartz et al., 2006 sourceNot checked yet

  Not checked in the free run.

May combine two claims.

The Cape Cod aquifer has six groundwater lenses, with their maximum elevations along the midpoint of the peninsula.

“The Cape Cod aquifer has six groundwater lenses, with their maximum elevations along the midpoint of the peninsula.”

• cites Masterson and Walter, 2009Not checked yet

  Not checked in the free run.

Probably not a substantial claim: may not pass S3 (load-bearing).

The California wells were much deeper than the wells tested on Cape Cod (median depth: 134 m versus 18 m).

“The California wells were much deeper than the wells we tested on Cape Cod (median depth: 134 m versus 18 m).”

May combine two claims.

Capture zones for domestic wells are smaller due to their smaller pumping volumes, and because passive wells such as domestic wells tend not to draw down the water table, they are expected to extend primarily in an upgradient direction.

“However, capture zones for domestic wells are smaller due to their smaller pumping volumes, and because passive wells such as domestic wells tend not to draw down the water table (Cole and Silliman, 1997), they are expected to extend primarily in an upgradient direction.”

• cites Cole and Silliman, 1997Not checked yet

  Not checked in the free run.

May combine two claims.

While boron and nitrate were strongly correlated (Spearman ρ = 0.7, p < 0.001), the combination of both can help distinguish wells that receive nitrate or boron from other sources.

“While [B] and [NO 3 -] were strongly correlated (Spearman ρ = 0.7, p b 0.001), the combination of both [B] and [NO 3 -] can help distinguish wells that receive NO 3 -or B from other sources.”

Probably not a substantial claim: may not pass S3 (load-bearing).

The authors were unable to test for correlations between total organic carbon and metrics of organic wastewater compound concentrations because total organic carbon was only detectable in five wells.

“We were unable to test for correlations between TOC and metrics of OWC concentrations because TOC was only detectable in five wells.”

May combine two claims.

Since capture zones for domestic wells are relatively small, they receive inputs from a limited number of individual homes, so chemical concentrations may be more variable depending on the characteristics of the wastewater from those individual homes.

“In addition, since capture zones for domestic wells are relatively small, they receive inputs from a limited number of individual homes, so chemical concentrations may be more variable depending on the characteristics of the wastewater from those individual homes.”

Probably not a substantial claim: may not pass S3 (load-bearing).

Heterogeneity in hydraulic conductivity can lead to small-scale variations in groundwater velocity and direction of groundwater flow.

“Heterogeneity in hydraulic conductivity can lead to small-scale variations in groundwater velocity and direction of groundwater flow (Cole and Silliman, 1997;Francke et al., 1998).”

• cites Cole and Silliman, 1997Not checked yet

  Not checked in the free run.

• cites Francke et al., 1998Not checked yet

  Not checked in the free run.

May combine two claims.

While NP and NPEOs have been measured at 10s to 100s of μg/L in septic tanks, some studies have found >90% removal in septic system drainfields.

“While NP and NPEOs have been measured at 10s to 100s of μg/L in septic tanks (Hinkle et al., 2005;Stanford and Weinberg, 2010), some studies have found N90% removal in septic system drainfields (Huntsman et al., 2006).”

• cites Hinkle et al., 2005 sourceNot checked yet

  Not checked in the free run.

• cites Stanford and Weinberg, 2010Not checked yet

  Not checked in the free run.

• cites Huntsman et al., 2006 sourceNot checked yet

  Not checked in the free run.

Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

In 26 shallow domestic wells in a sand and gravel aquifer, shallower wells (≤8 m) had higher concentrations of pharmaceuticals and were more likely to have reducing conditions.

“In 26 shallow domestic wells in a sand and gravel aquifer, shallower wells (≤ 8 m) had higher concentrations of pharmaceuticals and were more likely to have reducing conditions (Verstraeten et al., 2005).”

• cites Verstraeten et al., 2005 sourceNot checked yet

  Not checked in the free run.

May combine two claims.

For wells near the center of each lens, capture zones are likely to be relatively close, since groundwater primarily flows in a vertical direction, whereas for wells near the edges of each lens, capture zones are likely to be more distant, since the groundwater flows in a primarily horizontal direction.

“For wells near the center of each lens, capture zones are likely to be relatively close, since groundwater primarily flows in a vertical direction (Masterson and Walter, 2009), whereas for wells near the edges of each lens, capture zones are likely to more distant, since the groundwater flows in a primarily horizontal direction.”

• cites Masterson and Walter, 2009Not checked yet

  Not checked in the free run.

May combine two claims.

The weaker correlations between organic wastewater compound presence and nitrate suggest that while septic systems are the largest source of nitrate inputs into Cape Cod groundwater, there may be additional sources of nitrate to groundwater in the vicinity of some wells.

“Nevertheless, the weaker correlations between OWC presence and [NO 3 -] suggests that while septic systems are the largest source of NO 3 -inputs into Cape Cod groundwater, there may be additional sources of NO 3 -to groundwater in the vicinity of some wells.”

May combine two claims.

While some studies have found inverse associations between well depth and organic wastewater compound detections, well depth may not be a good predictor of organic wastewater compounds in deeper well systems and when comparing multiple aquifer types.

“Thus, while some studies have found inverse associations between well depth and OWC detections, well depth may not be a good predictor of OWCs in deeper well systems and when comparing multiple aquifer types.”

May combine two claims.

The two wells with the highest sodium concentrations (44, 45 mg/L) were not the wells with the highest boron concentrations, and the strong correlation between boron and organic wastewater compounds suggests that saltwater was the primary major source of boron to the wells tested in this study.

“However, the two wells with the highest sodium concentrations (44, 45 mg/L) were not the wells with the highest [B], and the strong correlation between [B] and OWCs suggests that saltwater was the primary major source of B to the wells tested in this study.”

Probably not a substantial claim: may not pass S3 (load-bearing).

In public supply wells, 500-m radius circular zones have been used to relate land use to concentrations of pollutants, such as volatile organic compounds.

“In public supply wells, 500-m radius circular zones have been used to relate land use to concentrations of pollutants, such as volatile organic compounds (Johnson and Belitz, 2009).”

• cites Johnson and Belitz, 2009Not checked yet

  Not checked in the free run.

Probably not a substantial claim: may not pass S3 (load-bearing).

Among over 3800 domestic wells in Wisconsin, USA, deeper wells tended to have lower nitrate concentrations.

“Among over 3800 domestic wells in Wisconsin, USA, deeper wells tended to have lower [NO 3 -] (Knobeloch et al., 2013).”

• cites Knobeloch et al., 2013Not checked yet

  Not checked in the free run.

May combine two claims.

While 1 mg/L nitrate is just one-tenth of the US drinking water standard, the findings suggest significant presence of organic wastewater compounds even in water with nitrate concentrations well below the drinking water standard.

“While 1 mg/L NO 3 is just one-tenth of the US drinking water standard, our findings suggest significant presence of OWCs even in water with [NO 3 -] well below the drinking water standard.”

Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

Acesulfame concentrations have previously been correlated with concentrations of PFASs in Swiss rivers, three pharmaceuticals in a wastewater-impacted river in Canada, two pharmaceuticals in groundwater impacted by septic systems, and two pharmaceuticals and a nicotine metabolite in groundwater impacted by a municipal wastewater plume.

“Acesulfame concentrations have previously been correlated with concentrations of: PFASs in Swiss rivers (Müller et al., 2011); three pharmaceuticals (carbamazepine, gemfibrozil, naproxen) in a wastewater-impacted river in Canada (Liu et al., 2014); two pharmaceuticals (carbamazepine, sulfamethoxazole) in groundwater impacted by septic systems; and two pharmaceuticals (carbamazepine, primidone) and”

• cites Müller et al., 2011 sourceNot checked yet

  Not checked in the free run.

• cites Liu et al., 2014 sourceNot checked yet

  Not checked in the free run.

• cites Van Stempvoort et al., 2013 sourceNot checked yet

  Not checked in the free run.

Probably not a substantial claim: may not pass S3 (load-bearing), S4 (based). May combine two claims.

Direction of groundwater flow can vary seasonally and can be influenced by pumping withdrawals from an aquifer.

“Direction of groundwater flow can vary seasonally and can be influenced by pumping withdrawals from an aquifer.”

Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

The method used to develop capture zones was based on typical groundwater conditions on Cape Cod and accounted for fluctuations in flow paths up to 30°.

“The method we used to develop capture zones was based on typical groundwater conditions on Cape Cod and accounted for fluctuations in flow paths up to 30° (Kerfoot and Horsley, 1988).”

• cites Kerfoot and Horsley, 1988Not checked yet

  Not checked in the free run.

May combine two claims.

The results from our wells show the complex interactions among multiple sources of OWCs and the limitations of attributing pollution to specific sources based on a single chemical indicator.

“The results from our wells show the complex interactions among multiple sources of OWCs and the limitations of attributing pollution to specific sources based on a single chemical indicator.”

Probably not a substantial claim: may not pass S3 (load-bearing).

PFAS concentrations in landfill leachate range from low ng/L to 100s of ng/L.

“PFAS concentrations in landfill leachate range from low ng/L to 100s of ng/L (Eggen et al., 2010;Huset et al., 2011;Clarke et al., 2015).”

• cites Eggen et al., 2010 sourceNot checked yet

  Not checked in the free run.

• cites Huset et al., 2011 sourceNot checked yet

  Not checked in the free run.

• cites Clarke et al., 2015 sourceNot checked yet

  Not checked in the free run.

Probably not a substantial claim: may not pass S2 (checkable).

In groundwater systems with multiple possible sources of OWCs into drinking water wells, a combination of indicators are needed to distinguish multiple sources.

“Thus in groundwater systems with multiple possible sources of OWCs into drinking water wells, a combination of indicators are needed to distinguish multiple sources.”

Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

Detailed hydrogeological models that account for small-scale variations in hydraulic conductivity and flow direction can be used to model flow paths for water pumped from domestic wells, but these detailed models often are not available to planners and developers making decisions about siting domestic wells.

“Detailed hydrogeological models that account for small-scale variations in hydraulic conductivity and flow direction can be used to model flow paths for water pumped from domestic wells, but these detailed models often are not available to planners and developers making decisions about siting domestic wells (Wilcox et al., 2010).”

• cites Wilcox et al., 2010 sourceNot checked yet

  Not checked in the free run.

Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

In addition to domestic wastewater, sources of OWCs into groundwater include landfill leachate, stormwater runoff, and wastewater from commercial and industrial sources.

“In addition to domestic wastewater, sources of OWCs into groundwater include landfill leachate, stormwater runoff, and wastewater from commercial and industrial sources (Erickson et al., 2014).”

• cites Erickson et al., 2014Not checked yet

  Not checked in the free run.

Probably not a substantial claim: may not pass S3 (load-bearing).

Epidemiological studies have shown associations between septic system density and diarrheal disease in children.

“Epidemiological studies have shown associations between septic system density and diarrheal disease in children (Borchardt et al., 2003) and have found septic systems to be a common contributing factor to disease outbreaks associated with untreated groundwater in the”

• cites Borchardt et al., 2003 sourceNot checked yet

  Not checked in the free run.

Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

Pharmaceuticals, personal care product ingredients, OPFRs, and PFASs have all been found in landfill leachates, with concentrations often varying by several orders of magnitude across locations.

“Pharmaceuticals, personal care product ingredients, OPFRs, and PFASs have all been found in landfill leachates, with concentrations often varying by several orders of magnitude across locations (Clarke et al., 2015).”

• cites Clarke et al., 2015 sourceNot checked yet

  Not checked in the free run.

May combine two claims.

Acesulfame was persistent for at least 15 years in a septic system plume, with concentrations of 8000-18,000 ng/L 200 m from the leach field.

“Acesulfame was persistent for at least 15 years in a septic system plume, with concentrations of 8000-18,000 ng/L 200 m from the leach field (Robertson et al., 2013).”

• cites Robertson et al., 2013 sourceNot checked yet

  Not checked in the free run.

Probably not a substantial claim: may not pass S3 (load-bearing).

Acesulfame and sucralose have been considered specific markers of wastewater in aquatic systems.

“While acesulfame and sucralose have been considered specific markers of wastewater in aquatic systems (Buerge et al., 2009), artificial sweeteners are also common in landfill leachate, with concentrations up to 85 μg/L acesulfame (Roy et al., 2014) and 620 μg/L sucralose (Clarke et al., 2015).”

• cites Buerge et al., 2009 sourceNot checked yet

  Not checked in the free run.

Probably not a substantial claim: may not pass S3 (load-bearing).

Epidemiological studies have found septic systems to be a common contributing factor to disease outbreaks associated with untreated groundwater in the US.

“and have found septic systems to be a common contributing factor to disease outbreaks associated with untreated groundwater in the US (Wallender et al., 2014).”

• cites Wallender et al., 2014 sourceNot checked yet

  Not checked in the free run.

May combine two claims.

Acesulfame is a sensitive marker of septic system impact and can be used as an indicator compound to identify wells that are likely impacted by other OWCs from domestic wastewater.

“In short, acesulfame is a sensitive marker of septic system impact and can be used as an indicator compound to identify wells that are likely impacted by other OWCs from domestic wastewater.”

Probably not a substantial claim: may not pass S3 (load-bearing).

Well W03 was located near an unsewered commercial area; wastewater from local businesses that use PFASs in paints, textiles coatings, or floor waxes may have been a source of PFASs to this well.

“This well was located near an unsewered commercial area; wastewater from local businesses that use PFASs in paints, textiles coatings, or floor waxes may have been a source of PFASs to this well.”

May combine two claims.

Acesulfame and sucralose underwent negligible removal during wastewater treatment and groundwater transport.

“Acesulfame and another artificial sweetener, sucralose, underwent negligible removal during wastewater treatment and groundwater transport, whereas two other artificial sweeteners, cyclamate and saccharin, showed ≥ 90% removal in wastewater treatment plants (Buerge et al., 2009), in a septic system plume (Robertson et al., 2013), and during riverbank filtration and artificial groundwater recharge”

• cites Buerge et al., 2009 sourceNot checked yet

  Not checked in the free run.

• cites Robertson et al., 2013 sourceNot checked yet

  Not checked in the free run.

• cites Scheurer et al., 2010 sourceNot checked yet

  Not checked in the free run.

Probably not a substantial claim: may not pass S3 (load-bearing).

Regulations provide minimum well-casing depths and minimum setback distances between wells and septic system tanks and leach fields (in the US, typically 15 m from septic tanks and 30 m from leach fields).

“Regulations provide minimum well-casing depths and minimum setback distances between wells and septic system tanks and leach fields (in the US, typically 15 m from septic tanks and 30 m from leach fields; Wilcox et al., 2010).”

• cites Wilcox et al., 2010 sourceNot checked yet

  Not checked in the free run.

Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

Combining information about when specific artificial sweeteners were introduced or withdrawn and the years of operation of a landfill can help distinguish multiple sources of OWCs in groundwater and can also be used to age-date landfill plumes.

“Combining information about when specific artificial sweeteners were introduced or withdrawn and the years of operation of a landfill can help distinguish multiple sources of OWCs in groundwater and can also be used to age-date landfill plumes (Van Stempvoort et al., 2011;Roy et al., 2014).”

• cites Van Stempvoort et al., 2011 sourceNot checked yet

  Not checked in the free run.

• cites Roy et al., 2014 sourceNot checked yet

  Not checked in the free run.

May combine two claims.

The median [B] in a study of landfill leachate was 4700 μg/L, which is ~20 times higher than septic tank effluent.

“The median [B] in a study of landfill leachate was 4700 μg/L (Clark and Piskin, 1977), which is ~20 times higher than septic tank effluent (Swartz et al., 2006), whereas the median concentration of total N (NO 3 -+ NH 4 + ) was 82 mg/L (Clark and Piskin, 1977), which is only around twice typical TN concentrations in septic tank effluent (Katz et al., 2010).”

• cites Clark and Piskin, 1977Not checked yet

  Not checked in the free run.

• cites Swartz et al., 2006 sourceNot checked yet

  Not checked in the free run.

Probably not a substantial claim: may not pass S3 (load-bearing).

Among four artificial sweeteners, acesulfame was detected at the highest concentrations in Swiss groundwater and surface waters.

“Among these four artificial sweeteners, acesulfame was detected at the highest concentrations in Swiss groundwater and surface waters (Buerge et al., 2009).”

• cites Buerge et al., 2009 sourceNot checked yet

  Not checked in the free run.

Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

In general, perfluorocarboxylic acids (e.g., PFOA) are more abundant than perfluorosulfonic acids (e.g., PFOS) and shorter-chain PFASs are more abundant than longer-chain in landfill leachates, although individual landfills have different relative abundances.

“These studies show that in general, perfluorocarboxylic acids (e.g., PFOA) are more abundant than perfluorosulfonic acids (e.g., PFOS) and shorter-chain PFASs are more abundant than longer-chain, although individual landfills have different relative abundances.”

• cites Eggen et al., 2010 sourceNot checked yet

  Not checked in the free run.

• cites Huset et al., 2011 sourceNot checked yet

  Not checked in the free run.

• cites Clarke et al., 2015 sourceNot checked yet

  Not checked in the free run.

Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

Acesulfame is commonly used in beverages, food, and toothpastes and can enter domestic wastewater through excretion and direct product disposal.

“Acesulfame is commonly used in beverages, food, and toothpastes (Buerge et al., 2009) and can enter domestic wastewater through excretion and direct product disposal (e.g., pouring out unconsumed beverages).”

• cites Buerge et al., 2009 sourceNot checked yet

  Not checked in the free run.

Probably not a substantial claim: may not pass S3 (load-bearing).

Artificial sweeteners are also common in landfill leachate, with concentrations up to 85 μg/L acesulfame and 620 μg/L sucralose.

“While acesulfame and sucralose have been considered specific markers of wastewater in aquatic systems (Buerge et al., 2009), artificial sweeteners are also common in landfill leachate, with concentrations up to 85 μg/L acesulfame (Roy et al., 2014) and 620 μg/L sucralose (Clarke et al., 2015).”

• cites Roy et al., 2014 sourceNot checked yet

  Not checked in the free run.

• cites Clarke et al., 2015 sourceNot checked yet

  Not checked in the free run.

May combine two claims.

Cyclamate and saccharin showed ≥90% removal in wastewater treatment plants, in a septic system plume, and during riverbank filtration and artificial groundwater recharge.

“whereas two other artificial sweeteners, cyclamate and saccharin, showed ≥ 90% removal in wastewater treatment plants (Buerge et al., 2009), in a septic system plume (Robertson et al., 2013), and during riverbank filtration and artificial groundwater recharge (Scheurer et al., 2010).”

• cites Buerge et al., 2009 sourceNot checked yet

  Not checked in the free run.

• cites Robertson et al., 2013 sourceNot checked yet

  Not checked in the free run.

• cites Scheurer et al., 2010 sourceNot checked yet

  Not checked in the free run.

Probably not a substantial claim: may not pass S3 (load-bearing).

There is growing recognition that unidentified PFAS precursors in contaminated groundwater can undergo transformation to form PFOS and PFOA.

“While little toxicological information is available for other PFASs, there is growing recognition that unidentified PFAS precursors in contaminated groundwater can undergo transformation to form PFOS and PFOA (Houtz et al., 2013).”

• cites Houtz et al., 2013 sourceNot checked yet

  Not checked in the free run.

May combine two claims.

In addition to septic systems, landfill leachate and wastewater from commercial development also may be sources of PFASs and other OWCs.

“In addition to septic systems, landfill leachate and wastewater from commercial development also may be sources of PFASs and other OWCs.”

May combine two claims.

Our results demonstrate the likelihood of OWC contamination in drinking water supplies in sand and gravel aquifers where groundwater discharges of wastewater are prevalent, especially in wells with elevated concentrations of nitrate and boron.

“Our results demonstrate the likelihood of OWC contamination in drinking water supplies in sand and gravel aquifers where groundwater discharges of wastewater are prevalent, especially in wells with elevated concentrations of nitrate and boron.”

May combine two claims.

The presence of OWCs in drinking water raises human health concerns, but a full evaluation of potential risks is limited by a lack of health-based guidelines and toxicological assessments.

“The presence of OWCs in drinking water raises human health concerns, but a full evaluation of potential risks is limited by a lack of health-based guidelines and toxicological assessments.”

May combine two claims.

These guidelines were developed for short-term exposures; the state of New Jersey has set a PFOA guideline for drinking water that is ten times lower.

“However, these guidelines were developed for short-term exposures; the state of New Jersey has set a PFOA guideline for drinking water that is ten times lower (Post et al., 2009).”

• cites Post et al., 2009 sourceNot checked yet

  Not checked in the free run.

May combine two claims.

Few guidelines for pharmaceuticals have been developed on the basis of toxicity studies, and toxicity assessment for pharmaceuticals may not include rigorous assessment of developmental toxicity, neuro-or immunotoxicity, endocrine toxicity, and carcinogenicity.

“However, few guidelines for pharmaceuticals have been developed on the basis of toxicity studies, and toxicity assessment for pharmaceuticals may not include rigorous assessment of developmental toxicity, neuro-or immunotoxicity, endocrine toxicity, and carcinogenicity (ICH, 2013).”

• cites ICH, 2013Not checked yet

  Not checked in the free run.

May combine two claims.

Nitrate testing is an inexpensive marker of OWCs in aerobic conditions and is readily available for domestic well owners and local boards of health, who can use the results to identify vulnerable wells for additional testing and enhanced source water protection.

“Nitrate testing is an inexpensive marker of OWCs in aerobic conditions and is readily available for domestic well owners and local boards of health, who can use the results to identify vulnerable wells for additional testing and enhanced source water protection.”

May combine two claims.

Elevated nitrate levels can indicate wastewater impact in aerobic conditions, while under anaerobic conditions other indicators, such as total nitrogen, boron, and artificial sweeteners, are more appropriate.

“Elevated nitrate levels can indicate wastewater impact in aerobic conditions, while under anaerobic conditions other indicators, such as total nitrogen, boron, and artificial sweeteners, are more appropriate.”

Classified as probably not a substantial claim. May combine two claims.

Since nitrate is a commonly measured drinking water contaminant, it is a useful screening tool for OWCs in domestic wells and target nitrate levels can be established to prioritize wells for additional water quality testing and enhanced source water protection.

“Since nitrate is a commonly measured drinking water contaminant, it is a useful screening tool for OWCs in domestic wells and target nitrate levels can be established to prioritize wells for additional water quality testing and enhanced source water protection.”

• AssumptionRests on an assumption: Local background nitrate concentration is tenfold lower than 1 mg/L NO3-N.