A pioneering study on endocrine disruptors (phthalates esters) in urban rivers of Bangladesh: An appraisal of possible risk assessment to ecology and human health

Abstract

Phthalate esters (PAEs) are plasticizers extensively used in industries and daily used products to soften Polyvinyl chloride (PVC) items. Phthalates, their occurrence, distribution, and ecological and human health effects have been studied long ago in other countries. However, the status of these compounds in Bangladesh is still unknown. To fill this study gap, an approach was taken to evaluate the current level of Phthalates in the rivers of Bangladesh. In this study, we assessed the environmental occurrence, spatial distribution, and possible risk to ecology and human health caused by this pollutant. Two heavily polluted industrial regions (Savar and Tongi) were selected, and seventeen surface water samples were collected from three urban rivers surrounding these areas. Samples were extracted via liquid-liquid extraction and analyzed by GC–MS. Status of 7 congeners of phthalates ((Dimethyl phthalate (DMP), Diethyl phthalate (DEP), Dibutyl phthalate (DBP), Benzyl butyl phthalate (BBP), Bis (2-ethylhexyl) phthalate (DEHP), Bis (2-ethylhexyl) adipate (DEHA), Di-n-octyl phthalate (DNOP)) were evaluated in this study. The observed concentrations in these two Study areas were alarmingly high compared to other countries. The estimated range of ∑7PAEs between the two sampling sites was 8.27 – 54.1µg/L and 24.6–156µg/L. In other countries, the concentration ranges in nano-grams. DEHP, a carcinogenic congener, was found in high concentration at the Savar region with a mean value of 6.01±4.43µg/L. In ecological risk assessment, potential environmental risks followed the following: DEHP > BBP > DBP > DEP > DMP. DEHP poses a "high" risk to all kinds of sensitive aquatic organisms in both study areas. Other congeners pose "moderate" to "high" risk. However, in human health risk assessment, the non-carcinogenic risk was found to be a 'low' to 'moderate' level. Still, the carcinogenic risk for DEHP was alarmingly high via oral and dermal contact for both adult groups and children.