Warmer water, high light intensity, lithium and microplastics: Dangerous environmental combinations to zooplankton and Global Health?

Lithium Pollution and Its Associated Health Risks in the Largest Lithium Extraction Industrial Area in China

Lithium (Li) is an important resource that drives sustainable mobility and renewable energy. Its demand is projected to continue to increase in the coming decades. However, the risk of Li pollution has also emerged as a global concern. Here, we investigated the pollution characteristics, sources, exposure levels, and associated health risks of Li in the Jinjiang River basin, the largest area for Li2CO3 production in China. Our results revealed the dominant role of Li extraction activities in the pollution of the river, with over 95% of dissolved Li in downstream river water being emitted from this source. Moreover, the Li concentration in aquatic plants (i.e., water hyacinth) and animals (i.e., fish) significantly increased from upstream to downstream areas, indicating a significant risk to local aquatic ecosystems. More importantly, our study found that local residents were suffering potential chronic noncarcinogenic health risks primarily from consuming contaminated water and vegetables. We also investigated the pollution characteristics of associated elements present in Li ores (e.g., Rb, Cs, Ni, and F-). By uncovering the remarkable impact of Li extraction activities on the Li content in ecosystems for the first time, our study emphasizes the importance of evaluating Li pollution from Li-related industrial activities, including mining, extraction, and recovery.

Alkali and alkaline earth elements in follicular fluid and the likelihood of diminished ovarian reserve in reproductive-aged women: a case‒control study

BACKGROUND

Imbalances in alkali elements (AEs) and alkaline earth elements (AEEs) cause reproductive disorders. However, it remains unclear whether AEs/AEEs in follicular fluid have a relationship with the serious reproductive disorder known as diminished ovarian reserve (DOR).

METHODS

A nested case‒control study was carried out in China. Follicular fluid samples from 154 DOR patients and 154 controls were collected and assessed for nine AEs/AEE levels. Both the mixed and single effects of the elements on DOR were estimated with a Bayesian kernel machine (BKMR) and logistic regressions.

RESULTS

The DOR group had higher median concentrations of Li, Na, and K in follicular fluid (all P values < 0.05). The logistic regression showed that compared with their lowest tertile, the high tertiles of K [OR:2.45 (1.67-4.43)], Li [OR: 1.89 (1.06-3.42)], and Cs [OR: 1.97 (1.10-3.54)] were significantly associated with the odds of DOR. The BKMR model reported that the DOR likelihood increased linearly across the 25th through 75th percentiles of the nine-AE/AEE mixture, while the AE group contributed more to the overall effect.

CONCLUSION

This study revealed an association in which the likelihood of DOR increased with higher overall concentrations of AE/AEEs in follicular fluid. Among the nine detected elements, K, Li, and Cs exhibited significant individual associations with DOR. We provide new clues for the environmental factors on female fertility decline.

TRIAL REGISTRATION

Retrospectively registered.

Potentially Toxic Elements' Accumulation in Relation to Sediment Physicochemical Attributes and Microplastic Content in Zayandeh-Rood River, Iran

Microplastics (MPs) are an emerging pollutant whose ability to adsorb potentially toxic elements (PTEs) poses a serious threat to aquatic ecosystems, including rivers. In highly developed basins, the abundance of MPs in river sediment is expected to be high, elevating the sedimentary accumulation of PTEs. This hypothesis was tested in the Zayandeh-Rood River, Central Iran, with 21 sediment sampling stations distributed along the entire river stretch. Results of sediment analysis showed significant variations in the abundance and size of MPs, with concentrations ranked as Ba (270.71 mg/kg) > Li (21.29 mg/kg) > Cs (2.50 mg/kg) > Be (1.44 mg/kg) > Sn (1.17 mg/kg) > Mo (1.06 mg/kg) > Ag (0.76 mg/kg), along with sediment physicochemical attributes such as EC, TOC, pH and grain size. MPs were identified in all sediment samples with a mean of 588 items/kg dry weight. Except for Ag, all other PTEs were classified as uncontaminated but exhibited increased enrichment downstream. According to the results of the generalized additive model (maximum R-sq of 0.766), the sedimentary concentration of the majority of PTEs is nonlinearly and positively associated with smaller and more abundant MPs. This study acknowledges that MPs might influence sediment porosity, permeability and structure, thereby directly affecting the settling dynamics of other particles, especially PTEs.

Negative Effects of Cyanotoxins and Adaptative Responses of Daphnia

The plethora of cyanobacterial toxins are an enormous threat to whole ecosystems and humans. Due to eutrophication and increases in lake temperatures from global warming, changes in the distribution of cyanobacterial toxins and selection of few highly toxic species/ strains are likely. Globally, one of the most important grazers that controls cyanobacterial blooms is Daphnia, a freshwater model organism in ecology and (eco)toxicology. Daphnia-cyanobacteria interactions have been studied extensively, often focusing on the interference of filamentous cyanobacteria with Daphnia's filtering apparatus, or on different nutritional constraints (the lack of essential amino acids or lipids) and grazer toxicity. For a long time, this toxicity only referred to microcystins. Currently, the focus shifts toward other deleterious cyanotoxins. Still, less than 10% of the total scientific output deals with cyanotoxins that are not microcystins; although these other cyanotoxins can occur just as frequently and at similar concentrations as microcystins in surface water. This review discusses the effects of different cyanobacterial toxins (hepatotoxins, digestive inhibitors, neurotoxins, and cytotoxins) on Daphnia and provides an elaborate and up-to-date overview of specific responses and adaptations of Daphnia. Furthermore, scenarios of what we can expect for the future of Daphnia-cyanobacteria interactions are described by comprising anthropogenic threats that might further increase toxin stress in Daphnia.