Correction to: Microplastics in seawater: sampling strategies, laboratory methodologies, and identification techniques applied to port environment

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Changes of CYP1A1, GST, and ALDH3 enzymes in hepatoma cell lines undergoing enhanced lipid peroxidation

Hepatoma cells show alterations in the response to oxidative stress (decreased lipid peroxidation) and in xenobiotic metabolism enzymes (decreased P450, increased GST and ALDH3). This study examined the effect of lipid peroxidation on the expression of the above enzymes in two rat hepatoma cell lines (MH 1C 1 and 7777). To induce oxidative stress, cells were exposed to arachidonic acid (to increase lipid peroxidation substrate) and/or to β-naphthoflavone (to increase CYP450), and treated with one dose of iron/histidine. The cells, that were still viable after the challenge, were refed with the culture medium and CYP1A1, GST, and ALDH3 enzymes monitored for 1, 6, 12, and 24 h. Treatments that increased markers indicative of lipid peroxidation are associated with a decrease in enzyme activities, which was permanent for CYP1A1 and transient for the other enzymes. We speculate from these data that aldehydic byproducts of lipid peroxidation may be responsible for these effects. Thus, restoration of lipid peroxidation in hepatoma cells seems to induce a rapid adaptation to oxidative stress, which is achieved by a simultaneous decrease of reactive oxygen species production and an increase in the two main enzymes involved in the removal of the aldehydic products of lipid peroxidation. Copyright (C) 2000 Elsevier Science Inc

Microplastic Contamination in Snow from Western Italian Alps

Recent studies have documented the presence of microplastics (MPs) in remote areas, including soils or sediments collected in mountain and glacier environments, but information on their presence in snow is scant. The present study aimed at exploring the presence of MPs in residual snow collected in four locations of the Aosta Valley (Western Italian Alps), with different accessibility and human presence. Overall, the µ-FTIR analyses confirmed the presence of 18 MPs in snow, 7 (39%) items were fibres, while 11 (61%) were fragments. Polyethylene (PE; 7 MPs) was the main polymer, followed by polyethylene terephthalate (PET; 3 MPs), high density PE (HDPE; 3 MPs), polyester (2 MPs), while only 1 MP made by low density PE, polypropylene and polyurethane were found. The mean (± SE) concentration of MPs in snow ranged between 0.39 ± 0.39 MPs/L and 4.91 ± 2.48 MPs/L, with a mean of 2.32 ± 0.96 MPs/L for the sampling locations. The concentration of MPs did not statistically differ among locations. Our results suggest that MPs presence in high-mountain ecosystems might depend on deposition through atmospheric precipitations or local sources due to human activities. For these reasons, policies aiming at reducing plastic use and dispersal in mountain areas may be effective in preventing local MP contamination