Under the influence of regulations: spatio-temporal trends of the UV filter 2-Ethylhexyl-4-methoxycinnamate (EHMC) in German rivers

Abstract Background Globally, 2-Ethylhexyl-4-methoxycinnamate (EHMC) is one of the most commonly used UV filters in sunscreen and personal care products. Due to its widespread usage, the occurrence of EHMC in the aquatic environment has frequently been documented. In the EU, EHMC is listed under the European Community Rolling Action Plan (CoRAP) as suspected to be persistent, bioaccumulative, and toxic (PBT) and as a potential endocrine disruptor. It was included in the first watch list under the Water Framework Directive (WFD) referring to a sediment PNEC of 200 µg/kg dry weight (dw). In the light of the ongoing substance evaluation to refine the environmental risk assessment, the objective of this study was to obtain spatio-temporal trends for EHMC in freshwater. We analyzed samples of suspended particulate matter (SPM) retrieved from the German environmental specimen bank (ESB). The samples covered 13 sampling sites from major German rivers, including Rhine, Elbe, and Danube, and have been collected since mid-2000s. Results Our results show decreasing concentrations of EHMC in annual SPM samples during the studied period. In the mid-2000s, the levels for EHMC ranged between 3.3 and 72 ng/g dw. The highest burden could be found in the Rhine tributary Saar. In 2017, we observed a maximum concentration ten times lower (7.9 ng/g dw in samples from the Saar). In 62% of all samples taken in 2017, concentrations were even below the limit of quantification (LOQ) of 2.7 ng/g dw. Conclusions The results indicate a general declining discharge of EHMC into German rivers within the last 15 years and correspond to the market data. Although the measured levels are below the predicted no-effect level (PNEC) in sediment, further research should identify local and seasonal level of exposure, e.g., at highly frequented bathing waters especially in lakes. In addition, possible substitutes as well as their potentially synergistic effects together with other UV filters should be investigated.

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Spatio-temporal trends in the flow and water quality: response of river Yamuna to urbanization

Environmental Monitoring and Assessment ◽

10.1007/s10661-021-08873-x ◽

2021 ◽

Vol 193 (3) ◽

Author(s):

Shweta Lokhande ◽

Vinod Tare

Keyword(s):

Water Quality ◽

Temporal Trends ◽

Spatio Temporal ◽

River Yamuna ◽

Quality Response

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Spatio-temporal trends and climatology of atmospheric chlorinated hydrocarbons over Pakistan

Arabian Journal of Geosciences ◽

10.1007/s12517-021-07809-6 ◽

2021 ◽

Vol 14 (15) ◽

Author(s):

Ahmad Hasnain ◽

Yong Zha ◽

Muhammad Zaffar Hashmi ◽

Fatima Rahim ◽

Yufeng He ◽

...

Keyword(s):

Temporal Trends ◽

Chlorinated Hydrocarbons ◽

Spatio Temporal

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Spatio-temporal impacts of aerial adulticide applications on populations of West Nile virus vector mosquitoes

Parasites & Vectors ◽

10.1186/s13071-021-04616-6 ◽

2021 ◽

Vol 14 (1) ◽

Author(s):

Karen M. Holcomb ◽

Robert C. Reiner ◽

Christopher M. Barker

Keyword(s):

West Nile Virus ◽

Temporal Trends ◽

Larval Habitat ◽

Post Treatment ◽

Additive Models ◽

Dispersal Ability ◽

Stochastic Variation ◽

West Nile ◽

Spatial Coverage ◽

Spatio Temporal

Abstract Background Aerial applications of insecticides that target adult mosquitoes are widely used to reduce transmission of West Nile virus to humans during periods of epidemic risk. However, estimates of the reduction in abundance following these treatments typically focus on single events, rely on pre-defined, untreated control sites and can vary widely due to stochastic variation in population dynamics and trapping success unrelated to the treatment. Methods To overcome these limitations, we developed generalized additive models fitted to mosquito surveillance data collected from CO2-baited traps in Sacramento and Yolo counties, California from 2006 to 2017. The models accounted for the expected spatial and temporal trends in the abundance of adult female Culex (Cx.) tarsalis and Cx. pipiens in the absence of aerial spraying. Estimates for the magnitude of deviation from baseline abundance following aerial spray events were obtained from the models. Results At 1-week post-treatment with full spatial coverage of the trapping area by pyrethroid or pyrethrin products, Cx. pipiens abundance was reduced by a mean of 52.4% (95% confidence intrval [CI] − 65.6, − 36.5%) while the use of at least one organophosphate pesticide resulted in a mean reduction of 76.2% (95% CI − 82.8, − 67.9%). For Cx. tarsalis, at 1-week post-treatment with full coverage there was a reduction in abundance of 30.7% (95% CI − 54.5, 2.5%). Pesticide class was not a significant factor contributing to the reduction. In comparison, repetition of spraying over three to four consecutive weeks resulted in similar estimates for Cx. pipiens and estimates of somewhat smaller magnitude for Cx. tarsalis. Conclusions Aerial adulticides are effective for achieving a rapid short-term reduction of the abundance of the primary West Nile virus vectors, Cx. tarsalis and Cx. pipiens. A larger magnitude of reduction was estimated in Cx. pipiens, possibly due to the species’ focal distribution. Effects of aerial sprays on Cx. tarsalis populations are likely modulated by the species’ large dispersal ability, population sizes and vast productive larval habitat present in the study area. Our modeling approach provides a new way to estimate effects of public health pesticides on vector populations using routinely collected observational data and accounting for spatio-temporal trends and contextual factors like weather and habitat. This approach does not require pre-selected control sites and expands upon past studies that have focused on the effects of individual aerial treatment events.

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Recessive Transition Mechanism of Arable Land Use Based on the Perspective of Coupling Coordination of Input–Output: A Case Study of 31 Provinces in China

Land ◽

10.3390/land10010041 ◽

2021 ◽

Vol 10 (1) ◽

pp. 41

Author(s):

Yi Lou ◽

Guanyi Yin ◽

Yue Xin ◽

Shuai Xie ◽

Guanghao Li ◽

...

Keyword(s):

Land Use ◽

Evaluation Model ◽

Arable Land ◽

Temporal Trends ◽

Mainland China ◽

Input Output ◽

Transition Mechanism ◽

Input And Output ◽

Spatio Temporal ◽

Arable Land Use

In the rapid process of urbanization in China, arable land resources are faced with dual challenges in terms of quantity and quality. Starting with the change in the coupling coordination relationship between the input and output on arable land, this study applies an evaluation model of the degree of coupling coordination between the input and output (D_CCIO) on arable land and deeply analyzes the recessive transition mechanism and internal differences in arable land use modes in 31 provinces on mainland China. The results show that the total amount and the amount per unit area of the input and output on arable land in China have presented different spatio-temporal trends, along with the mismatched movement of the spatial barycenter. Although the D_CCIO on arable land increases slowly as a whole, 31 provinces show different recessive transition mechanisms of arable land use, which is hidden in the internal changes in the input–output structure. The results of this study highlight the different recessive transition patterns of arable land use in different provinces of China, which points to the outlook for higher technical input, optimized planting structure, and the coordination of human-land relationships.

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