Screening of antimicrobials, fragrances, UV stabilizers, plasticizers and preservatives in sewage treatment plants (STPs) and their risk assessment in India.

Community/industrial wastewater is the prime source of anthropogenic chemicals, its treatment is often a daunting task and unaffordable for many countries. Emerging Contaminants (ECs) have been drained into wastewater after continuous use/misuse and Conventional treatments in STPs do not remove them completely. ECs including antimicrobial agents, synthetic musks, Benzotriazole UV stabilizers (BUVSs), plasticizers, and preservatives are frequently reported in environment, and cause health effects to non-target organisms. Monitoring of ECs is important to understand their status in aquatic environment. Hence, it was aimed to monitor ECs (n = 21) from 11 STPs in Tamil Nadu, India. The detection frequency of most of these analytes was >90%. Antimicrobials ranged from 247 to 22,714 ng/L and 11-14,369 ng/L in influents and effluents, respectively. The synthetic musks were in the order of Tonalide > Galaxolide > Musk Ketone. BUVSs ranged from 4 to 1632 ng/L (influents) and < LOD to 29,853 ng/L (effluents). Concentration of phthalates in influents and effluents were < LOD - 11,311 ng/L and < LOD - 17,618 ng/L, respectively. Parabens were found in the order of Prophyl > Methyl > Ethyl > Butyl in influents and Methyl > Prophyl > Butyl > Ethyl in effluents. Mass loads of ECs through STPs were found as antimicrobials > plasticizers > fragrances > BUVSs > Preservatives. This study reveals increasing usage of ECs and inadequate treatment processes at STPs in India. Also helps to adopt suitable treatment processes to remove ECs from wastewater and to reuse the wastewater.

Occurrence of triclocarban and benzotriazole ultraviolet stabilizers in water, sediment, and fish from Indian rivers.

Triclocarban and benzotriazole ultraviolet stabilizers (BUVSs) are listed as high production volume synthetic chemicals, used extensively in personal care products. Many of these chemicals persist in the aquatic environment as micropollutants. Knowledge on their fate in freshwater ecosystems is still lacking, especially in the Indian Rivers. Our intention is to study the seasonal distribution, hazard quotient, risk assessment, and bioaccumulation of triclocarban and BUVSs (UV-9, UV-P, UV-326, UV-327, UV-328, and UV-329) during wet and dry seasons in water, sediment and fish from the Kaveri, Vellar, and Thamiraparani rivers in Tamil Nadu State, India. Triclocarban and BUVSs were identified in all matrices analysed. Triclocarban was found in water, sediment, and fish up to 1119ng/L, 26.3ng/g (dry wt.), and 692ng/g (wet wt.), respectively. Among BUVSs, UV-329 was found up to 31.3ng/L (water samples), UV-327 up to 7.3ng/g (sediment samples), and UV-9 up to 79.4ng/g (fish samples). The hazard quotient (HQenv.) for triclocarban in surface water was found to be at risk level (HQenv. >1) in the Kaveri, and Thamiraparani rivers during dry season. Bioaccumulation factors indicate that target compounds (triclocarban and BUVSs) could bio-accumulate in organisms.

GC-MS determination of phthalate esters in human urine: A potential biomarker for phthalate bio-monitoring.

Six phthalic acid esters (PAEs) in human urine sampled randomly from three districts (Erode, Thanjavur, and Perambalur) in Tamil Nadu State and a Union Territory (Pondicherry) in India were quantified. We determined gender-wise, age-wise and location-wise distribution of PAEs and measured estrogenic activity of urine by molecular docking. Bis(2­ethylhexyl) phthalate (DEHP) was the predominant phthalic acid ester found and had a recovery of 104.5% (ultrasonic extraction at 15 min). Gender-wise (pregnant women: 185 ng/mL, children: 156 ng/mL, female: 151 ng/mL, and male: 138 ng/mL), age-wise (1-20 y: 157 ng/mL, 21-40 y: 156 ng/mL, and >40 y: 146 ng/mL), location-wise (urban: 154 ng/mL, and rural: 151 ng/mL), and region-wise (Erode district: 185 ng/mL, Thanjavur district: 155 ng/mL, Perambalur district: 117 ng/mL, and Pondicherry: 135 ng/mL) differences with total mean of Σ6 PAEs were found. The molecular docking study showed a high negative binding energy of PAEs with microbial receptors. Based on the results we conclude that urine could be used as an ideal biomarker to understand PAEs exposure in humans.