Trace metal exposure and risk assessment of local dominant fish species in the Beijiang River Basin of China: A 60 years' follow-up study.

The Beijiang River, one of the Pearl River tributaries located in Guangdong, China, plays a critical role in providing water and fishery resources for the Pearl River Delta and receiving a large amount of domestic and industrial wastewater. However, due to the lack of historical monitoring data, we are unable to fully understand the relationship between the industrial and agricultural development and the environment. In this study, fish specimens collected from the Beijiang River Basin over a span of nearly 60 years (1963-2021) are used as research objects and the concentrations of ten trace metals (TMs) in two locally dominant fish species were determined by an inductively coupled plasma mass spectrometer. The human health risks caused by consuming fishes were assessed. Results show a correlation between the levels of TMs in fish muscle and the degree of industrialization. The concentrations of Cr, Mn, Ni, and Cu peaked during the period of 1981-1983, when China's industrial development was rapidly expanding while the environmental protection facilities were incomplete. However, with the implementation of Ecological Civilization policy, the levels of Cr, Mn, Ni, Cu, Cd, and Ba showed a downward trend in the period from 2018 to 2021. Cu concentrations in both fish muscle and viscera exhibit analogous change patterns across different periods, indicating that Cu serves as a significant indicator of TM pollution in the Beijiang River Basin. The presence of TMs in fish muscle often exhibits long-term enrichment, while those in the viscera demonstrate short-term accumulation. Based on the estimated daily intake, the target hazard quotient (THQ), and total THQ value, the overall health risk associated with TMs in fish from the Beijiang River Basin is low. However, certain TMs in the fish rebounded during 2018-2021, posing a potential risk for aquatic biology and ecosystems, which is worth our attention.

What adverse health effects will environmental heavy metal co-exposure bring us: based on a biological monitoring study of sanitation workers.

To investigate the relationship between health effect profile and co-exposure to heavy metal, 254 sanitation workers from Guangzhou, China, were recruited. Ten urinary metals were determined by inductively coupled plasma mass spectrometry. Parameters of physical examination, including blood lipid metabolism, renal function, blood pressure, and lung function, were tested for each participant. The hazard quotients (HQs) of eight heavy metals were evaluated. Cobalt, copper (Cu), molybdenum (Mo), nickel (Ni), and tin (Sn) demonstrated the top five associations with human health with the ∑19ß as 2.220, 1.351, 1.234, 0.957, and 0.930, respectively. Most physical examination parameters of workers were under the normal ranges, except the levels of forced mid expiratory flow rate (MMEF75/25), the maximum expiratory flow rate at 25% vital capacity (MEF25) and apolipoprotein B in the first quartile, and the level of uric acid in the third quartile of sanitation works. Moreover, Cu was significantly associated with diastolic pressure, pulse, and high density lipid (p < 0.05). Each unit increase in Mo level was related to a 120% increase odd ratio (OR) of abnormal of systolic pressure, but was significantly and negatively correlated with high density lipoprotein and apolipoprotein A, suggesting that Mo exposure may be a risk factor of cardiovascular disease. Each unit increase in Ni and Sn levels was associated with an increased OR of abnormal rate of MMEF75/25 and MEF25 (p < 0.001), suggesting the increasing risks of respiratory diseases. Sanitation workers exposed to Ni and Pb alone had no carcinogenic risks (HQ < 1). However, 23.8%, 34.6%, and 87.3% of sanitation workers confronted non-carcinogenic risks when exposed to Cu, Mo alone (HQ > 1), or co-exposed to the four heavy metals (HI > 1). Our study preliminarily revealed the potential sensitive health indicators of heavy metal co-exposure, which will provide beneficial health protection suggestions for the occupational populations.