Feasibility of Biological Effective Monitoring of Chrome Electroplaters to Chromium through Analysis of Serum Malondialdehyde

Health Risk Assessment of Occupational Exposure to Hexavalent Chromium in Iranian Workplaces: a Meta-analysis Study

Occupational exposure to hexavalent chromium (Cr⁺⁶) has reported in different industries. The Cr⁶⁺ has the carcinogenic and non-carcinogenic effects. The aim of this study was to provide a meta-analysis and health risk assessment of occupational exposure to Cr⁶⁺ in Iranian workplaces. Databases including Scopus, Web of Sciences (WOS), and Scientific Information Database (SID), as a national database, were searched from 2000 to February 2021. The related studies to occupational exposure to Cr⁶⁺ were selected by Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) protocol. Lung cancer and non-cancer risk (nasal mucosal irritation, atrophy, and perforation) of Cr⁶⁺ were estimated by Environmental Protection Agency (EPA) method, based on the Monte Carlo simulation (MCS). Also, the results of spirometry and biomonitoring of previous studies were reviewed. We found 14 articles based on inclusion criteria. Pooled concentration of Cr⁶⁺ was estimated 0.037 ± 0.002 mg/m³ which was higher than the recommended exposure limit by the ACGIH (0.002 mg/m³). The mean lung cancer risk was estimated to be 5.49E-2, which was considerable risk. In the Cr⁶⁺-exposed workers, all parameters of pulmonary function had decreased. The level of Cr⁶⁺ in urinary and blood samples was higher than threshold limit. Results indicated that exposure to Cr⁶⁺ and its health risk were more than recommended exposure limit. The results of present study could be helpful for health policy maker to control exposure to Cr⁶⁺ in workplaces.

Biomarkers of effect as determined in human biomonitoring studies on hexavalent chromium and cadmium in the period 2008-2020

A number of human biomonitoring (HBM) studies have presented data on exposure to hexavalent chromium [Cr(VI)] and cadmium (Cd), but comparatively few include results on effect biomarkers. The latter are needed to identify associations between exposure and adverse outcomes (AOs) in order to assess public health implications. To support improved derivation of EU regulation and policy making, it is of great importance to identify the most reliable effect biomarkers for these heavy metals that can be used in HBM studies. In the framework of the Human Biomonitoring for Europe (HBM4EU) initiative, our study aim was to identify effect biomarkers linking Cr(VI) and Cd exposure to selected AOs including cancer, immunotoxicity, oxidative stress, and omics/epigenetics. A comprehensive PubMed search identified recent HBM studies, in which effect biomarkers were examined. Validity and applicability of the markers in HBM studies are discussed. The most frequently analysed effect biomarkers regarding Cr(VI) exposure and its association with cancer were those indicating oxidative stress (e.g., 8-hydroxy-2'-deoxyguanosine (8-OHdG), malondialdehyde (MDA), glutathione (GSH)) and DNA or chromosomal damage (comet and micronucleus assays). With respect to Cd and to some extent Cr, β-2-microglobulin (B2-MG) and N-acetyl-β-D-glucosaminidase (NAG) are well-established, sensitive, and the most common effect biomarkers to relate Cd or Cr exposure to renal tubular dysfunction. Neutrophil gelatinase-associated lipocalin (NGAL) and kidney injury molecule (KIM)-1 could serve as sensitive biomarkers of acute kidney injury in response to both metals, but need further investigation in HBM studies. Omics-based biomarkers, i.e., changes in the (epi-)genome, transcriptome, proteome, and metabolome associated with Cr and/or Cd exposure, are promising effect biomarkers, but more HBM data are needed to confirm their significance. The combination of established effect markers and omics biomarkers may represent the strongest approach, especially if based on knowledge of mechanistic principles. To this aim, also mechanistic data were collected to provide guidance on the use of more sensitive and specific effect biomarkers. This also led to the identification of knowledge gaps relevant to the direction of future research.

Medical Diagnostic Tests: A Review of Test Anatomy, Phases, and Statistical Treatment of Data

Diagnostic tests are approaches used in clinical practice to identify with high accuracy the disease of a particular patient and thus to provide early and proper treatment. Reporting high-quality results of diagnostic tests, for both basic and advanced methods, is solely the responsibility of the authors. Despite the existence of recommendation and standards regarding the content or format of statistical aspects, the quality of what and how the statistic is reported when a diagnostic test is assessed varied from excellent to very poor. This article briefly reviews the steps in the evaluation of a diagnostic test from the anatomy, to the role in clinical practice, and to the statistical methods used to show their performances. The statistical approaches are linked with the phase, clinical question, and objective and are accompanied by examples. More details are provided for phase I and II studies while the statistical treatment of phase III and IV is just briefly presented. Several free online resources useful in the calculation of some statistics are also given.