Occurrence and distribution of estrogenic chemicals in river waters of Malaysia

Objective
This study investigated the occurrence of eight endocrine-disrupting compounds (EDCs) in river water across five major regions in Malaysia, which are recognized as emerging micropollutants in the environment.
Methods
The water samples were collected from surface water of Klang River, Pahang River, Kuantan River, Kelantan River and Terengganu River from Malaysia. The samples were extracted by liquid–liquid extraction using hexane and ethyl acetate and loaded on silica column for column chromatography. Gas chromatography–flame ionization detector was used to determine the concentration of the target compounds.
Results
The maximum concentration of E1, E2, E3, EE2, 1,2,4-triazole, MP, 3,4,4-trichlorocarbanilide and BPA detected is 26.5 ng/L, 15.5 ng/L, 3.6 μg/L, 68.8 ng/L, 6.5 ng/L, 5.75 ng/L, 392.5 ng/L and 37 μg/L, respectively. The high discharge of various emerging organic pollutants in the Klang River estuary ecosystem was caused by heavy industrial, plantation, residential and commercial activities from urbanized and populated cities. Overall, the occurrences show a higher concentration of EDCs when compared to developed countries. Other rivers such as Kuantan, Terengganu, Pahang and Kelantan are known as the major sources of water supply for domestic, industrial and agricultural purposes.
Conclusions
Eight endocrine-disrupting chemicals were detected and estimated in five rivers of Malaysia. These target compounds are widely present in various rivers in the range of ND to 37 μg/L. The difference of occurrence of EDCs in these selected sampling sites reflects the distinct usage patterns of various chemicals, pesticide, cosmetic products, drugs all over Malaysia. The presence of BPA, E1 and E3 was observed to be a major contributor of endocrine disruptors.