Archives of Environmental Contamination and Toxicology最新文献

The aim of this work was to relate the contribution of mine-derived airborne particulate matter to Ca, Fe, Mn and S content and distribution in Punctelia hypoleucites transplanted to Bajo de la Alumbrera, an important open-pit mine in Catamarca, Argentina. Lichen samples were transplanted to four monitoring sites: two sites inside the mine perimeter and two sites outside the mine. After three months, elemental distribution in samples was analyzed by microparticle-induced X-ray emission (microPIXE), and elemental concentration was determined by specific techniques: Ca and Fe by instrumental neutron activation analysis, Mn by inductively coupled plasma atomic emission spectrometry and S by a turbidimetric method. A differential distribution of S and Ca in thalli transplanted in-mine sites was detected compared to that of samples transplanted outside-mine sites. An overlap of Fe and S in the upper cortex of the apothecium section was observed, leading to infer a mineral association of both elements. Similar association was observed for Ca and S. In addition to these results, the significantly higher concentration detected for S and Mn in in-mine site samples suggests a contribution of Fe, S, Ca and Mn of mining origin to the content and distribution of these elements in P. hypoleucites. MicroPIXE complemented with Mössbauer spectroscopy analysis determined the presence of pyrite particles together with other iron-bearing minerals displaying different degrees of oxidation. These results point to a mining origin of the airborne particulate matter trapped by the lichen thalli transplanted to Bajo de la Alumbrera. These findings indicate that P. Hypoleucites acts as an excellent air quality biomonitor in the Bajo de la Alumbrera mine area.

Predation presents specific behavioral characteristics for each species, and the interaction between prey and predator influences the structuring of the food web. Concerning insects, predation can be affected in different ways, such as exposure to chemical stressors, e.g., pesticides. Therefore, analyses were carried out of the effects of exposure to insecticide fipronil and the herbicide 2,4-D on predation, parameters of food selectivity, and the swimming behavior of two neotropical predatory aquatic insects of the families Belostomatidae (giant water bugs) and larvae of Libellulidae (dragonfly). These predatory insects were exposed for 24 h to a commercial formulation of the chlorophenoxy herbicide, 2,4-D at nominal concentrations of 200, 300, 700, and 1400 μg L⁻¹, and to a commercial formulation of the phenylpyrazole insecticide, fipronil at nominal concentrations of 10, 70, 140, and 250 µg L⁻¹. In a control treatment, the insects were placed in clean, unspiked water. At the end of the exposure, the maximum swimming speed of the predators was evaluated. Afterward, the predators were placed in clean water in a shared environment for 24 h with several prey species, including the cladoceran Ceriodaphnia silvestrii, larvae of the insect Chironomus sancticaroli, the amphipod Hyalella meinerti, the ostracod Strandesia trispinosa, and the oligochaete Allonais inaequalis for 24 h. After this period, the consumed prey was counted. The results reveal that predators from both families changed prey consumption compared with organisms from the control treatment, marked by a decrease after exposure to fipronil and an increase in consumption caused by 2,4-D. In addition, there were changes in the food preferences of both predators, especially when exposed to the insecticide. Exposure to fipronil decreased the swimming speed of Belostomatidae individuals, possibly due to its neurotoxic effect. Exposure to the insecticide and the herbicide altered prey intake by predators, which could negatively influence the complex prey–predator relationship and the functioning of aquatic ecosystems in contaminated areas.

The presence of selected polybrominated diphenyl ethers (BDE-28, -47, -99, -100, -153, -154, and -183) was investigated in human milk samples collected from first-time mothers living in Zagreb, capital of Croatia. Samples from 2020 and 2010 were analyzed, and the first temporal comparison between the profiles and levels of these compounds in this area was obtained. A statistically significant difference between mass fractions depending on the sampling year was observed only for BDE-99, with values in 2020 higher than in 2010. BDE-153, whose median value (0.25 and 0.26 ng g⁻¹ lipid weight (l.w.) in 2010 and 2020, respectively) did not decrease in the 10-year period, was the most frequently detected congener in samples from both years. ΣPBDEs ranged from < LOD to 3.53 ng g⁻¹ l.w. (median 0.25 ng g⁻¹ l.w.), and from 0.14 to 6.75 ng g⁻¹ l.w. (median 0.55 ng g⁻¹ l.w.) in 2010 and 2020, respectively. Maternal age and reported fish consumption had no effect on observed PBDE mass fractions, while for BDE-153, positive significant correlation (p > 0.05) was observed of its detected mass fraction with mother’s body mass index (BMI) before pregnancy and after childbirth. Infants median estimated daily intake (EDI) via milk ingestion for ΣPBDE was higher in 2020 (3.221 ng kg⁻¹ bw day⁻¹) compared to 2010 (1.429 ng kg⁻¹ bw day⁻¹), but both values were well below threshold value, indicating that human milk consumption in this specific case is unlikely to raise health risks to infants.

Heavy metals are naturally omnipresent in aquatic systems. Excess amounts of heavy metals can accumulate in organisms of pollution impacted systems and transfer across a food web. Analysing the food web structure and metal contents of the organisms can help unravel the pathways of biomagnification or biodilution and gain insight in trophic linkages. We measured heavy metals and other elements in mussel bank detritus and organisms of the Biesbosch reservoirs (the Netherlands) and linked those to stable isotopic signatures. The heavy metal contents (cadmium, copper, lead, and zinc) were often lowest in benthivorous, omnivorous and piscivorous species (mainly fish); whereas, phosphorus contents were lower in the autotrophs. Mussel bank detritus contained the highest amounts of heavy metals. The heavy metals were negatively correlated with δ¹⁵N values. For selenium no clear trend was observed. Furthermore, there was a negative correlation between fish length and some heavy metals. Based on all 20 analysed elemental contents, similarities between species became apparent, related to niche or habitat. This study confirms that elemental contents of species can differ between feeding guilds and/or species, which can be attributed to metabolic and physiological processes. The organisms in higher trophic levels have adaptations preventing metal accumulation, resulting in lower contents. Within the fish species biodilution occurs, as most metal contents were lowest in bigger fish. Overall, the metals did not seem to biomagnify, but biodilute in the food web. Metal analyses combined with isotopic signatures could thus provide insights in metal transfer and possible trophic linkages within a system.

Bromoform is the most prominent, relatively long-lived chlorination by-product in condenser effluents from seawater-based power plant cooling systems. There are few reports on the potential toxicity of this trihalomethane to marine phytoplankton. We investigated this using a marine diatom, Chaetoceros lorenzianus as the model organism. The study was conducted by exposing the diatom to bromoform concentrations 0, 50, 100, 150, 250, 500 and 1000 µg/L for exposure time of 3 and 24 h. The mode of action of bromoform was examined using endpoints which include chlorophyll a fluorescence, cell viability by SYTOX® green stain and genotoxicity by comet assay. The relative fluorescence unit and percent viability changed significantly at all concentrations in duration of study. The 24-h IC₅₀ for viability and chlorophyll was estimated to be 255.6 µg/L and 343.5 µg/L, respectively. The tail DNA of 5–20% observed by comet assay indicated low-level DNA damage. Bromoform manages to target cell membrane and internal machinery, DNA and chlorophyll molecule of cell, leading to cause damage at multiple physiological levels. Based on the present data, the current discharge levels of bromoform 50–250 µg/L cause significant impact on the phytoplankton under investigation. However, the impact can be limited under actual field conditions wherein mixing of cooling water with natural water bodies is considered. Nevertheless, more studies are required to understand the toxicological response of organisms to bromoform, so that discharge levels can be continued to be kept within safe levels.

The mining and smelting site soils in South China present excessive Cd pollution. However, the transport behavior of Cd in the highly weathered acidic soil layer at the lead–zinc smelting site remains unclear. Here, under different conditions of simulated infiltration, the migration behavior of Cd²⁺ in acid smelting site soils at different depths was examined. The remodeling effect of Cd²⁺ migration behavior on microbial community structure and the dominant microorganisms in lead–zinc sites soils was analyzed using high-throughput sequencing of 16S rRNA gene amplicons. The results revealed a specific flow rate in the range of 0.3–0.5 mL/min that the convection and dispersion have no obvious effect on Cd²⁺ migration. The variation of packing porosity could only influence the migration behavior by changing the average pore velocity, but cannot change the adsorption efficiency of soil particles. The Cd has stronger migration capacity under the reactivation of acidic seepage fluid. However, in the alkaline solution, the physical properties of soil, especially pores, intercept the Cd compounds, further affecting their migration capacity. The acid-site soil with high content of SOM, amorphous Fe oxides, crystalline Fe/Mn/Al oxides, goethite, and hematite has stronger ability to adsorb and retain Cd²⁺. However, higher content of kaolinite in acidic soil will increase the potential migration of Cd²⁺. Besides, the migration behavior of Cd²⁺ results in simplified soil microbial communities. Under Cd stress, Cd-tolerant genera (Bacteroides, Sphingomonas, Bradyrhizobium, and Corynebacterium) and bacteria with both acid-Cd tolerance (WCHB 1-84) were distinguished. The Ralstonia showed a high enrichment degree in alkaline Cd²⁺ infiltration solution (pH 10.0). Compared to the influence of Cd²⁺ stress, soil pH had a stronger ability to shape the microbial community in the soil during the process of Cd²⁺ migration.

Alterations in ivermectin (IVM, 22,23-dihydro avermectin B1a+22,23-dihydro avermectin B1b) toxicokinetics following P-glycoprotein (P-gp) induction by clotrimazole (CTZ) were examined in rainbow trout (Oncorhynchus mykiss) to assess the potential importance of P-gp activity levels in xenobiotic distribution and kinetics in fish. Control and fish pretreated with CTZ (30 µmol/kg) were administered 175 µg/kg ³H-IVM into the caudal vasculature. At various time points (0.25, 0.5, 1, 3, 24, 48, 96, and 168 h) following injection, tissues (blood, liver, kidney, gill, intestines, brain [5 regions], eye, gonad and fat) were removed analyzed for IVM-derived radioactivity. IVM concentration declined in blood, liver, kidney and gill, and concentrations in other tissues remained constant over the sampling period. The highest measured concentrations were found in kidney, followed by liver, with the lowest values found in brain, eye and gonad. The highest % of the administered dose was found in the liver and kidney in the immediate hours post-administration, and in the intestines and fat at 24 h post-administration. P-gp induction by CTZ did not alter IVM distribution or any calculated toxicokinetic parameter (AUC, mean residence time, T_1/2, clearance rate, volume of distribution), suggesting that P-gp induction may be limited or that P-gp plays a lesser role in xenobiotic kinetics in fish compared to mammals.

The areal distributions of the soil organochlorine pesticide (OCP) levels were investigated at adjacent and surrounding sites of the obsolete pesticide stockpile warehouse in Kocaeli, Türkiye. OCP levels in soil at neighboring sampling locations (positioned at 0.4 to 3 km from the stockpile) varied from 0.4 to 9 µg/kg and 4.2 to 2226 µg/kg (dry weight) for ΣHCHs and ΣDDXs, respectively. Levels at adjacent locations (positioned within 20 m from the stockpile) were considerably higher, varying from 74 to 39,619 µg/kg and 1592 to 30,419 µg/kg for ΣHCHs and ΣDDXs, respectively. Levels of OCPs dropped abruptly with the horizontal distance from the stockpile and had different transect profiles. The enantiomer fractions (EFs) near the stockpile range from 0.494 to 0.521, 0.454 to 0.515, and 0.483 to 0.533 for α-HCH, o,p′-DDT, and o,p′-DDD, respectively. These near-racemic EFs suggested that observed soil OCP levels were mainly influenced by recent emissions from the stockpile. A comparison of OCP compositions observed in the soil at the present study with the technical HCHs and DDTs revealed that the material in the stockpile primarily contains byproducts that were discarded during DDT and Lindane production at the adjacent plant instead of their technical mixtures.

The seeds of Annona glabra L., an invasive plant in Vietnam, were first employed as a new biosorbent for the adsorption of methylene blue (MB) from aqueous media. The characterizations of the material using FT-IR, SEM, nitrogen adsorption–desorption analysis, and point of zero charge reveals that it possesses a rough and irregular surface, various polar functional groups, and pH_pzc of 5.5. Certain adsorption conditions including adsorbent dose, solution pH, contact time, and initial concentration of MB were found to affect adsorption efficiency. The kinetic data are well fitted with pseudo-second-order model with the adsorption rate of 0.002 g mg⁻¹ min⁻¹ and initial rate of 4.46 mg g⁻¹ min⁻¹. For the adsorption isotherm, three nonlinear models were used to analyze the experiment data, including Langmuir, Freundlich, and Temkin. The results indicate that the Langmuir model best describes the adsorption of Annona glabra L. seeds powder (AGSP) with a maximum adsorption capacity of 98.0 mg g⁻¹. The investigation underpins the adsorption mechanism, whereby the electrostatic attraction between positively charged MB and negatively charged surface of AGSP is expected to be the predominant mechanism, together with hydrogen bonding and pi–pi interaction. These results make AGSP an interesting biosorbent concerning its environmental friendliness, cost-effectiveness, and relatively high dye adsorption capacity.

Ground applications of adulticides via a specialized truck-mounted sprayer are one of the most common practices for control of flying adult mosquitoes. Aerosols released to drift through a targeted area persist in the air column to contact and kill flying mosquitoes, but may also drift into adjacent areas not targeted by the applications where it may affect nontarget insects such as imperiled butterflies. This study compared the risk of permethrin to adult mosquitoes and adult butterflies to assess the likelihood that the butterflies would be affected following such sprays. Permethrin toxicity values were determined for Aedes aegypti and Culex quinquefasciatus (LD50s of 81.1 and 166.3 ng/g dw, respectively) and then combined with published toxicity data in a species sensitivity distribution for comparison with published permethrin toxicity data for adult butterflies. The sensitivity distributions indicated adult butterflies and mosquitoes are similarly sensitive, meaning relative risk would be a function of exposure. Exposure of adult butterflies and adult mosquitoes to permethrin was measured following their exposure to ULV sprays in an open field. Average permethrin concentrations on adult mosquitoes (912–38,061 ng/g dw) were typically an order of magnitude greater than on adult butterflies (110–11,004 ng/g dw) following each spray, indicating lower risk for butterflies relative to mosquitoes. Despite lower estimated risk, 100% mortality of adult butterflies occurred following some of the sprays. Additional studies could help understand exposure and risk for butterflies in densely vegetated habitats typical near areas treated by ULV sprays.