Anthropogenic-induced ecological risks on marine ecosystems indicated by characterizing emerging pollutants in Pearl River Estuary, China.

Anthropogenic Contaminants of Emerging Concern (CECs) in marine environments have raised significant concerns. Yet, analyses detailing their origins, fate, and environmental effects are limited. This study employs an integrated non-target screening methodology to elucidate CECs existence across 46 sampling sites in the Pearl River Estuary (PRE) of the South China Sea. Assisted by advanced liquid chromatography-high resolution mass spectrometry, we discovered 208 chemicals in six usage categories, with pesticides (33 %) and pharmaceuticals (29 %) predominating. Several CECs drew attention for their consistent detections, profound abundance, and significant ecotoxicities. The wide detection of them at offshore sites further implies that anthropogenic activities may contribute to large-scale contamination. Meanwhile, distinct distribution patterns of CECs across PRE are evident in semi-quantitative results, indicating regional anthropogenic influences. Identified transformation products may establish a novel and non-negligible negative contribution to ecology through elevated environmental toxicities, exemplified by HMMM and atrazine. Based on the ecological risks, we compiled a prioritized list of 21 CECs warranting intensified scrutiny. Our findings indicate the introduction of various CECs into the South China Sea via PRE, emphasizing the urgent necessity for ongoing surveillance of discharged CECs at estuary areas and assessment of their marine ecological consequences.

Integrating data dependent and data independent non-target screening methods for monitoring emerging contaminants in the Pearl River of Guangdong Province, China.

The occurrence of Contaminants of Emerging Concern (CECs) in the Pearl River of Guandong province, China, was characterized using a nontarget screening (NTS) strategy combining both data dependent and data independent acquisition techniques. Our analysis identified 620 unique compounds, including pharmaceuticals (137), pesticides (124), industrial materials (68), personal care products (32), veterinary drugs (27), plasticizers or flame retardants (11), etc. Out of these compounds, 40 CECs were found with a detection frequency of over 60 %, including diazepam, a well-known drug to treat anxiety, insomnia, convulsion, etc., which had the highest detection rate at 98 %. Risk quotients (RQs) were calculated for CECs identified with high confidence (Level 1, confirmed with authentic standards), and it was found that 12 CECs had RQs > 1, with notable concern for pretilachlor (detection frequency: 48 %; 0.8-19.0 ng/L), bensulfuron-methyl (86 %, 3.1-56.2 ng/L), imidacloprid (80 %, 5.3-62.8 ng/L) and thiamethoxam (86 %, 9.1-99.9 ng/L), which exhibited RQs exceeding the threshold of concern (RQ > 1) at 46-80 % of sampling sites. Additionally, tentative identification of potential structurally related compounds provided valuable insight into the parent-product relationships in complex samples. This study highlights the importance and urgency of using NTS for CECs in the environment and presents a novel data sharing approach, which facilitates other scientists to assess, investigate further, and perform retrospective analyses.