Environmental threats from the accumulation of plastic trash are getting worse.  It is robust, lightweight, corrosion-resistant, affordable, and durable. Microorganisms play a significant role in protecting our environment by degrading plastic wastes that are harmful either naturally or by chemical modification.  The current study aims to investigate the biodegradation of synthetic polyethylene through the utilization of a laboratory bioreactor. Various types of additives were introduced to the soil samples before subjecting them to a 30-day UV treatment. The degradation of polyethylene was shown through a reduction in weight following a 24-week incubation period with certain bacterial strains. Experimental findings have revealed that models subjected to UV radiation exhibit the highest degree of vulnerability and degradation. Approximately 52% of polyethylene (PE) films underwent degradation when exposed to soil enhanced with peat moss. In contrast, only 40% and 45% of PE films were destroyed when subjected to garden soil that was untreated and treated with UV radiation, respectively. In contrast, the addition of husk resulted in a 48% to 53% reduction in weight for PE films that were buried for the same duration of the experiment.  The highest level of effectiveness was achieved by the disintegration of the plastic material that was introduced into the soil along with organic fertilizers, resulting in a value of 56.60%. The weight loss outcomes have been substantiated by the utilization of the Atomic Force Electron Microscope (AFM) images, which exhibited the highest magnitude in the experimental model using soil supplemented with fertilizers.

A waste-oil contaminated site situated near a river is supposed to be cleaned-up by means of different but complementary methods. On the basis of a research project, target values have been developed in close cooperation between the participant parties for the saturated and the unsaturated soil layers. The clean-up targets are introduced and discussed.

International audience | Although high PAH content and detection of PAH-degraders, the PAH biodegradation is limited in aged-contaminated soils due to low PAR availability (i.e., 1%). Here, we tried to experimentally increase the soil PAH availability by keeping both soil properties and contamination composition. Organic extract was first removed and then re-incorporated in the raw soil as fresh contaminants. Though drastic, this procedure only allowed a 6-time increase in the PAH availability suggesting that the organic constituents more than ageing were responsible for low availability. In the re-contaminated soil, the mineralization rate was twice more important, the proportion of 5-6 cycles PAH was higher indicating a preferential degradation of lower molecular weight PAH. The extraction treatment induced bacterial and fungal community structures modifications, Pseudomonas and Fusarium solani species were favoured, and the relative quantity of fungi increased. In re-contaminated soil the percentage of PAH-dioxygenase gene increased, with 10 times more Gram negative representatives.

As a result of this study the overload by pollutants and low quality of canal water in the zone downstream of Vrbas and Srbobran towns (Serbia, Yugoslavia) has been recorded. Regarding to started work on demudification of canal bottom in the industrial zone of Vrbas town, in the course of 2000 the additional investigations of mud profile downstrean of wastewater discharge into the canal have been done. In the investigated mud samples the extremely high number of organotrophic bacteria was found (up to 1.7 x 10**10 cfu/ml), but also high number of conditionally pathogenic bacteria (opportunistic bacteria) was recorded. Also, the high number of fecal (thermo-tolerant) coliform bacteria (Escherichia coli and Klebsiella - Enterobacter - Citrobacter group of bacteria), as well as the presence of colifags was found. Such findings indicate possible bad consequences to the health of humans contacting this mud, as well as to the ground water quality, indirectly, via drainage water.

Fine particulate matter (PM₂.₅) has been associated with risk of oral and respiratory diseases. However, the biological mechanisms of adverse oral and respiratory health response to PM₂.₅ fluctuation have not been well characterized. This study aims to explore the relationships of PM₂.₅ with airway inflammation, salivary biomarkers and buccal mucosa microbiota. We performed a panel study among 40 college students involving 4 follow-ups from August to October 2021 in Hefei, Anhui Province, China. Health outcomes included fractional exhaled nitric oxide (FeNO), salivary biomarkers [C-reactive protein (CRP), cortisol, lysozyme and alpha-amylase] and buccal mucosa microbial diversity. Linear mixed-effect models were applied to explore the cumulative impacts of PM₂.₅ on health indicators. PM₂.₅ was positively correlated with FeNO, CRP, cortisol and alpha-amylase, while negatively with lysozyme. Per 10-μg/m³ increase in PM₂.₅ was linked to maximum increments in FeNO of 10.71% (95%CI: 2.01%, 19.41%) at lag 0–24 h, in CRP of 7.10% (95%CI: 5.39%, 8.81%) at lag 0–24 h, in cortisol of 1.25% (95%CI: 0.44%, 2.07%) at lag 0–48 h, and in alpha-amylase of 2.12% (95%CI: 0.53%, 3.71%) at lag 0–24 h, while associated with maximum decrement in lysozyme of 0.53% (95%CI: 0.12%, 0.95%) at lag 0–72 h. Increased PM₂.₅ was linked to reduction in the richness and evenness of buccal microbe and o_Bacillales and o_Bacteroidales were identified as differential microbes after PM₂.₅ inhalation. Bio-information analysis indicated that immunity system pathway was the most important enriched abundant process altered by PM₂.₅ exposure. In summary, short-term PM₂.₅ exposure may impair oral and respiratory health by inducing inflammatory and stress responses, weakening immune function and altering buccal mucosa microbial diversity.