The lasting effects of wastewater irrigation: Evaluating alkylphenols accumulation in soil and potential health risks for farmers and local communities

• The 4-nonylphenol concentration in agricultural soil ranged from 5.3 to 89.0 mg kg -1 . • The 4-t-octylphenol in agricultural soil ranged from non-detectable to 0.264 mg kg -1 . • 4-nonylphenol levels in effluent wastewater ranged from 0.42 to 14.61 μg/L. • The 4-t-octylphenol in effluent wastewater ranged from 0.0127 to 0.0635 μg/L. • Study shows health risks from alkylphenols contamination for children and adults. Reclaimed wastewater is being utilized extensively in agriculture worldwide to tackle water scarcity due to the climate change. However, this practice raises concerns about endocrine-disrupting compounds (EDCs) like alkylphenols (APs) in soil and their potential risks to human health. This study examined the presence of APs in both secondary treated wastewater (STW) and agricultural soil, which had been irrigated with wastewater for about 40 years. The study found significant accumulation of 4-Nonylphenol (4-NP) and 4‑tert-Octylphenol (4-t-OP), in the agricultural soil compared to non-irrigated soil. The research also calculated the estrogenic equivalence (EEQ) of APs in agricultural soil and wastewater. The concentrations of APs in the agricultural soil were found to range from 5.33 to 89.0 mg kg -1 dry weight (dw) for 4-NP and from non-detectable levels to 0.2643 mg kg -1 dw for 4-t-OP, while in wastewater, the concentrations ranged from 0.42 to 14.61 μg/L for 4-NP and 0.0127 to 0.0635 μg/L for 4-t-OP. The study highlighted the potential health risks posed by accidental ingestion of contaminated soil and wastewater with APs, especially for children and adults who might face chronic, subchronic, or short-term exposure. The HQ for exposure to 4-NP in contaminated soil was significantly higher than 1 for chronic exposures involving individuals such as farmers, ranging from 3.35×10 –4 to 3.31×10 2 . For subchronic exposures affecting individuals like workers, the health risk ranged from 1.01×10 –8 to 1.21×10 1 . The hazard index values for chronic exposure to APs for adults exceed 1. There is a potential non-carcinogenic risk for children, with maximum health risk values significantly exceeding 1.