Spatial distribution, ecotoxicity and human health assessment of nutrients and heavy metals in river sediment under urbanization – A study case of Yitong River, China

ABSTRACT

We investigated the contents and distributions of nutrients and heavy metals in sediment from the Yitong River. The main aims were to analyze heavy metals speciation and evaluate their bioavailability, in order to assess the risks they pose to both ecosystem and human health. The average total nitrogen (TN), total phosphorus (TP), organic matter (OM) and Cd, Cr, Cu, Ni, Pb and Zn contents were 1747.69, 895.58, 75103, 0.19, 75.64, 33.61, 47.17, 56.65 and 159.91 mg kg⁻¹, respectively. Results from acid-extraction fraction analysis showed that the proportions of Cd and Zn ranged from 3.78% to 30.20% and 5.31% to 30.74%, respectively. Health risk assessment model showed the risk index values of children and adults were 0.412 and 0.059, respectively, indicating a minimal threat to human health. Multivariate statistical analyses revealed that TN and TP may have similar sources and could be attributed to combined sewer overflows, while Cr, Cu, Ni and Zn were primarily derived from industrial pollution sources. Toxicity bioassay tests demonstrated that the majority of sediment samples were classified as non-toxic. However, 25% of the samples showed slight toxicity towards Vibrio qinghaiensis Q67, while 7% of the samples exhibited slight toxicity towards Daphnia magna. Based on these findings, it is necessary to implement pollution control measures and conduct assessments of aquatic ecological risks in sediments from urban rivers. These results can be used to develop effective strategies for the management and governance of aquatic sediments.

KEYWORDS:

• Urban River
• heavy metal
• nutrient
• biotoxicity
• sediment
• source distribution

Acknowledgments

We thank Gabrielle David, PhD, from Liwen Bianji (Edanz) (www.liwenbianji.cn/) for editing the English text of a draft of this manuscript.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Author contribution

Fujie Zhai and Xudong Deng: data collection and analysis, literature review, language services. Chao Zhang: manuscript writing, literature review, language services as well as research funding support. Baoqing Shan: Provide manuscript content and ideas.

Data availability statement

The data used in this study are trustworthy and available upon reasonable request from the corresponding author

Supplementary material

Supplemental data for this article can be accessed online at https://doi.org/10.1080/26395940.2023.2248384

Additional information

Funding

This study was funded by the National Natural Science Foundation of China (Grant No. 41907267) and the National Key Research and Development Program of China (2022YFC3204003). We also acknowledge support received from Youth Innovation Promotion Association CAS (grant no. 2017059).