Onsite wastewater treatment systems (OWTSs) and private wells are commonly used in Eastern North Carolina, USA. Water from private wells is not required to be tested after the initial startup, and thus persons using these wells may experience negative health outcomes if their water is contaminated with waste-related pollutants including bacteria, nitrate or synthetic chemicals such as hexafluoropropylne oxide dimer acid and its ammonium salt (GenX). Water samples from 18 sites with OWTSs and groundwater wells were collected for nitrate, Escherichia coli (E. coli), total coliform, and GenX concentration analyses. Results showed that none of the 18 water supplies were positive for E. coli, nitrate concentrations were all below the maximum contaminant level of 10 mg L-1, and one well had 1 MPN 100 mL-1 of total coliform. However, GenX was detected in wastewater collected from all 18 septic tanks and 22% of the water supplies tested had concentrations that exceeded the health advisory levels for GenX. Water supplies with low concentrations of traditionally tested for pollutants (nitrate, E. coli) may still pose health risks due to elevated concentrations of emerging contaminants like GenX and thus more comprehensive and routine water testing is suggested for this and similar persistent compounds.
Drawing on responses from 238 beachgoers who have visited a Georgia (U.S. state) beach in the past three years, this study asks respondents about their knowledge of beach water quality monitoring, awareness of beach health advisories, perception of water quality, and expected responses upon learning of a beach's water pollution advisory. Binomial logistic regression finds that the only demographic predictor of respondents who would completely stop visiting a beach with an advisory is whether the respondent is a visitor or resident (year-round or part-time). Nearly 40% of visitors would not come to a beach with an advisory compared to 13.4% of residents. Most respondents report they would continue to visit a beach but would stay out of the water and stop harvesting seafood from the beach's waters. More than a third (36.1%), however, are unaware Georgia regularly monitors beach water for water quality, and 41.2% have never read a beach sign warning of contaminated water or seafood. Alarmingly, just over half view aesthetic factors such as no litter, no odor, and clear water as criteria for defining whether beach water is safe.
The present study found that ∼80 million people in India, ∼60 million people in Pakistan, ∼70 million people in Bangladesh, and ∼3 million people in Nepal are exposed to arsenic groundwater contamination above 10 μg/L, while Sri Lanka remains moderately affected. In the case of fluoride contamination, ∼120 million in India, >2 million in Pakistan, and ∼0.5 million in Sri Lanka are exposed to the risk of fluoride above 1.5 mg/L, while Bangladesh and Nepal are mildly affected. The hazard quotient (HQ) for arsenic varied from 0 to 822 in India, 0 to 33 in Pakistan, 0 to 1,051 in Bangladesh, 0 to 582 in Nepal, and 0 to 89 in Sri Lanka. The cancer risk of arsenic varied from 0 to 1.64 × 1-1 in India, 0 to 1.07 × 10-1 in Pakistan, 0 to 2.10 × 10-1 in Bangladesh, 0 to 1.16 × 10-1 in Nepal, and 0 to 1.78 × 10-2 in Sri Lanka. In the case of fluoride, the HQ ranged from 0 to 21 in India, 0 to 33 in Pakistan, 0 to 18 in Bangladesh, 0 to 10 in Nepal, and 0 to 10 in Sri Lanka. Arsenic and fluoride have adverse effects on animals, resulting in chemical poisoning and skeletal fluorosis. Adsorption and membrane filtration have demonstrated outstanding treatment outcomes.
The study objective was to evaluate human faecal contamination impacts in the Yal-ku lagoon in the Mexican Caribbean and to estimate adenovirus infection and illness risks associated with recreational exposure during water activities. A total of 20 water samples (10 from each site × two sites) (50 L) were collected monthly over a period of 12 months from two selected sampling sites in the swimming area of the Yal-ku lagoon. The occurrence of faecal-associated viruses was explored, and human adenovirus (HAdV) and pepper mild mottle virus (PMMoV) concentrations were quantified. A quantitative microbial risk assessment (QMRA) model was used to estimate exposure and subsequent adenovirus infection and illness risk for 1 h of swimming or snorkelling. Somatic and F + -specific coliphages occurred in 100% of the samples. Both HAdV and PMMoV were detected at a 60% frequency thereby indicating persistent faecal inputs. PMMoV concentrations (44-370 GC/L) were relatively lower than the concentrations of HAdV (64-1,000 GC/L). Estimated mean adenovirus risks were greater for snorkelling than for swimming by roughly one to two orders of magnitude and estimated mean illness risks for snorkelling were >32/1,000. Human faecal contamination is frequent in the Yal-ku lagoon, which is associated with human gastrointestinal illness.