Biomarker considerations in monitoring petrogenic pollution using the mussel Mytilus galloprovincialis

Abstract

Mussels are worldwide bioindicators in pollution monitoring since they fulfil the requirements for being good sentinels. However, some methodological concerns arise in the use of particular biomarkers, particularly those displaying low enzymatic rates and/or limited responsiveness to chemicals and biological-related variability. In the present study, the suitability of oxidative stress and detoxification parameters when using mussels as sentinels of polycyclic aromatic hydrocarbons (PAHs) pollution is addressed. Present results show that the S9 subcellular fraction of the digestive gland in mussels is an adequate and convenient matrix where to measure most pollution related biomarkers. Furthermore, this work constitutes the first evidence of the potential suitability of using particular carboxylesterase (CE) activities in determining PAHs exposure in mussels. This fact could imply the replacement of more controversial cytochrome P450 components (phase I oxidation), which are only measurable in microsomal fractions, by CEs (measured in S9 fractions) as good alternatives for phase I reactions in PAH-exposed mussels. Some methodological considerations, such as the need of including commercial purified proteins in biomarker determinations for quality assurance, are evaluated.

The use of an in vitro approach to assess marine invertebrate carboxylesterase responses to chemicals of environmental concern

“…The formation of p-nitrophenol (pNPA and pNPB) was recorded at 405 nm as described in Hosokawa and Satoh (2005), while naphthol (αNA and αNB) was measured at 235 nm according to the Mastropaolo and Yourno (1981) method. Assay dilutions for hCE1 and hCE2 for each particular substrate have been recently described in Solé et al, (2020). Specific multi-well plates were used for assays using the visible (Nunc) or the ultraviolet (Grenier) wavelength ranges.…”

“…E0412) were also included in the analyses using the 4 selected substrates. More detail on the CE inhibition test and purified protein CE dilutions is described elsewhere (Solé and Sanchez-Hernandez, 2018;Solé et al, 2020).…”

Threats of Pollutants Derived from Electronic Waste to Marine Bivalves: The Case of the Rare‐Earth Element Yttrium

“…The coincident responses of both biotransformation enzymes (CbEs and GSTs), with a decrease at the lowest Y dosage (5 µg/L) support their role as Phase I and II steps in detoxification. The positive relationship between the two enzymes in bivalves has been studied by Solé et al (2020) in polycyclic aromatic hydrocarbon-contaminated environments, and they suggested CbEs as a good indicator of Phase I metabolism in bivalves. In fact, in the present study, these two biomarkers have also shown a significant positive Pearson correlation value (r = 0.679, p < 0.05), supporting this proposal.…”

Biomarker responses and metabolism in Lumbricus terrestris exposed to drugs of environmental concern, an in vivo and in vitro approach

“…E0162 and hCE2,ref. E0412) were also included as quality controls of the in vitro protocol (Solé et al, 2020;. Briefly, it consisted on 15 min incubation of the diluted S9 fraction with the selected contaminants at the same 100 µM concentration and the residual CE activity measured as describe in section 2.2.2.…”

“…It is also used in many ecotoxicological studies where its suitability has been validated (Gonzalez Vejares et al, 2010;Sanchez-Hernandez et al, 2014). Many of these toxicity studies support the use of biochemical biomarkers such as acetylcholinesterase (AChE) as an indicator of neurotoxicity, glutathione S-transferase (GST) suggestive of enhanced detoxification activities and carboxylesterases (CEs) as specific indicators of pesticide exposure but also involved in detoxification of many agrochemicals and drugs (Sanchez-Hernandez, 2006Solé et al, 2020;). An adaptation of the OECD directive protocol 207 on "Earthworm, Acute Toxicity Tests" mostly based on Eisenia spp.…”