Occurrence of perfluoroalkyl acids in environmental waters in Vietnam

Duong et al. observed higher levels of PFAS in rainy seasons possibly due to stormwater runoff.

“Duong et al. (2015) also observed higher levels of PFAS in rainy seasons possibly due to the influence of stormwater runoff”

PFAS contamination was reported in multiple parts of Asia including India, Bangladesh, Vietnam, Singapore, Thailand, Malaysia, and others.

“PFAS contamination was reported in multiple parts of Asia including India, Bangladesh, Vietnam, Singapore, Thailand, Malaysia, and many others (Duong et al., 2015; Habibullah-Al-Mamun et al., 2016; Kim et al., 2012; Lam et al., 2017; Nguyen et al., 2011; Sakurai et al., 2016; Sharma et al., 2016; Yeung et al., 2009).”

Maximum concentrations of PFOA and PFOS in groundwater in Vietnam were 4.5 and 8.2 ng L−1, respectively.

“Duong et al. (2015) focused on the occurrence of PFAS in Vietnam and reported that PFOA and PFOS were among the most detected PFAS in urban river waters at maximum concentrations of 18 and 5.3 ng L−1, respectively; while the maximum concentrations of these pollutants detected in groundwater were 4.5 and 8.2 ng L−1, respectively.”

PFAS concentrations in Vietnam were subject to seasonal variation, with relatively higher concentrations in the rainy season versus the dry season.

“Their results indicated that PFAS concentrations were subject to seasonal variation as concentrations were relatively higher in the rainy season versus the dry season suggesting that stormwater runoff could be a potential non-point source of PFAS pollution in Vietnam.”

PFOS was detected in 59% of surface water samples and 45% of groundwater samples in Vietnam.

“PFOA was detected in 98% of surface water samples and 36% of groundwater samples, while PFOS was detected in 59% of surface water samples and 45% of groundwater samples.”

Stormwater runoff could be a potential non-point source of PFAS pollution in Vietnam.

“Their results indicated that PFAS concentrations were subject to seasonal variation as concentrations were relatively higher in the rainy season versus the dry season suggesting that stormwater runoff could be a potential non-point source of PFAS pollution in Vietnam.”

Duong et al. (2015) reported that PFOA and PFOS were among the most detected PFAS in urban river waters in Vietnam, with maximum concentrations of 18 and 5.3 ng L−1, respectively.

“Duong et al. (2015) focused on the occurrence of PFAS in Vietnam and reported that PFOA and PFOS were among the most detected PFAS in urban river waters at maximum concentrations of 18 and 5.3 ng L−1, respectively; while the maximum concentrations of these pollutants detected in groundwater were 4.5 and 8.2 ng L−1, respectively.”

PFOA concentrations in the Red River were generally low, ranging from 0.16 to 0.52 ng L−1.

“PFOA concentrations in the Red River were generally low, ranging from 0.16–0.52 ng L−1, and PFOS was detected at only one location at a concentration of 0.21 ng L−1 (Duong et al., 2015).”

PFOA was detected in 98% of surface water samples and 36% of groundwater samples in Vietnam.

“PFOA was detected in 98% of surface water samples and 36% of groundwater samples, while PFOS was detected in 59% of surface water samples and 45% of groundwater samples.”

PFOS was detected at only one location in the Red River, at a concentration of 0.21 ng L−1.

“PFOA concentrations in the Red River were generally low, ranging from 0.16–0.52 ng L−1, and PFOS was detected at only one location at a concentration of 0.21 ng L−1 (Duong et al., 2015).”