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Long-term exposure to potentially toxic elements (PTEs) increases carcinogenic and non-carcinogenic risks in the exposed population. The current study was conducted with the aims of meta-analysis concentrations of PTEs including Arsenic (As), Cadmium (Cd), Lead (Pb), Mercury (Hg), Nickel (Ni) and Copper (Cu) in the water resources and human health risk assessment for adult males and female consumers in China. Search was performed in international databases including Web of Science, Scopus, PubMed, Embase and Google Scholar (gery literature) from January 1, 2005 to April 1, 2024. The concentration of PTEs was meta-analyzed using random effects model in water resources (surface water and groundwater) and location of study (urban and rural locations) subgroups. Human health risk assessment due to PTEs in water from ingestion and dermal contact pathways was estimated using target hazard quintet (THQ) and carcinogenic (CR) in adult males and female consumers in China. One hundred and twenty-six papers with 237 data-reports (n = 13,083) were included in this study. The rank order of PTEs based on pooled concentration was As (12.6530 µg/l) > Cu (11.1810 µg/l)> Ni (2.4950 µg/l) > Pb (2.0660 µg/l) > Cd (0.5370 µg/l) > Hg (0.3600 µg/l). The rank order of PTEs based on percentage studies higher than standard limits was As (28.37 %) > Pb (16.67 %) > Hg (11.86 %) > Ni (9.91 %) > Cd (7.48 %) > Cu (2.38 %). The pooled concentration of Pb, Ni, Hg and Cu in surface water resources was higher than groundwater but concentration of As and Cd in groundwater water was higher than surface water. The rank order of PTEs based on percentage studies with the high non-carcinogenic risk (THQ ≥ 1) for male was As (30.49 %) > Cd (8.09 %)> Hg (6.90 %) > Ni (3.60 %)> Cu (3.39 %) > Pb (2.50 %) and for female, As (29.78 %) > Cd (8.09 %)> Hg (6.90 %) > Cu (3.39 %) > Ni (2.70 %)> Pb (1.25 %). The rank order of PTEs based on percentage studies with high carcinogenic risk (TCR ≥ 1E-4) for male was As (60.28 %) > Cd (33.33 %) and for female, As (56.73 %) > Cd (29.93 %). Therefore, to reduce the carcinogenic and non-carcinogenic risks of PTEs especially As, continuous monitoring and control release of As into water resources through novel approaches is recommended.

Antibiotics residues even low concentrations increases human health risk and ecological risk. The current study was conducted with the aims of meta-analysis concentrations of antibiotics in river water including amoxicillin (AMX), tetracyclines (TCN), sulfamethoxazole (SMX), ciprofloxacin (CIP), trimethoprim (TMP), azithromycin (AZM) and amoxicillin (AMX) and estimates human health and ecological risks. Search was performed in databases including Scopus, PubMed, Web of Science, Embase, Science direct, Cochrane, Science Direct, Google Scholar were used to retrieve scientific papers from January 1, 2004 to June 15, 2024. The concentration of antibiotics residues was meta-analyzed using random effects model in water river water based on type of antibiotics subgroups. Human health risk assessment from ingestion and dermal contact routs was estimated using target hazard quotient (THQ), total target hazard quotient (TTHQ), carcinogenic (CR) and ecological hazard quotient (EHQ) of antibiotics in river water was estimated using monte carlo simulations (MCS) model. Sixty-two papers on antibiotics in river water with 272 data-reports (n = 28,522) were included. The rank order of antibiotics residues in river water based on pooled concentration was SMX (66.086 ng/L) > CIP (26.005 ng/L) > TCN (17.888 ng/L) > TMP (6.591 ng/L) > AZM (2.077 ng/L) > AMX (0.029 ng/L). The overall pooled concentration of antibiotics residues in river water was 24.262 ng/L, 95 %CI (23.110–25.413 ng/L). TTHQ for adults and children due to antibiotics in water was 2.41E-3 and 2.36E-3, respectively. The sort of antibiotics based on their quota in TTHQ for adults and children was AMX > CIP > TMP > AZM > TCN > SMX. Total CR in adults and children was 2.41E-03 and 2.36E-03, respectively. The sort of antibiotics based on percentile 95 % EHQ was SMX (7.70E+03) > TCN (7.63E+01) > TMP (7.03E-03) > CIP (2.86E-03) > AMX (5.71E-04) and TEHQ values due to antibiotics in river water in China was equal to 7.78E+03. Current study suggests that conduct effective monitoring and water quality control plans to reduce concentration of antibiotics especially SMX, TCN, and CIP in river water of China.

The fast development of urbanization emits huge amount of domestic wastewater, of which the high contents of chemical oxygen demand(COD), NH4-N, total nitrogen and phosphorous lead to the difficulty in their complete removal and the recycling of the water. To solve this problem, the simulated domestic sewage treatment efficiency was investigated via scenedesmus quadricauda and chlorella pyrenoidosa in terms of COD, NH4-N, total nitrogen (TN), and total phosphorous (TP). The influence of the dosage of the two microalgae (100 mg/L and 200 mg/L) on wastewater treatment and the relationship of the indexes COD, NH4-N, TN, and TP with handling time were examined. The surface morphology and chemistry before and after water treatment were characterized through SEM and FTIR, respectively. Scenedesmus quadricauda and chlorella pyrenoidosa show significant removal efficiency towards COD, with removal rates of 77.92% and 80.43%, respectively. Chlorella pyrenoidosa shows better NH4-N (58.34%) and TP (51.09%) removal efficiency than scenedesmus quadricauda for NH4-N (43.66%) and TP (41.52%). Scenedesmus quadricauda shows better TN removal efficiency (78.33%) than chlorella pyrenoidosa (76.67%). The results might provide fundamental and technical support for the application of algal microorganism.