Toxicology and Industrial Health

Mornagui, Bessem; Rezg, Raja; Neffati, Fadoua; Najjar, Mohamed Fadhel; Rejeb, Ahmed

doi: 10.1177/07482337231166490pmid: 36951826

There is considerable evidence that Bisphenol S (BPS) induces various toxicological effects and is an industrial health issue. However, little data are available on the in vivo effects of BPS on the liver, a major target of drug toxicity. In this study, we evaluated the potential harmfulness of low levels of BPS in the liver of male mice. Also, we investigated the interaction between BPS and peroxisome proliferator-activated receptor-gamma (PPARγ) by computational docking approach. PPARγ is a member of the superfamily of nuclear hormone receptors. It acts as a transcription factor and regulates the genes involved in lipid and glucose metabolism and in inflammation and necrosis. Mice were exposed to BPS, in drinking water at 25, 50, and 100 μg/kg for 10 weeks. The protocol was started after weaning. At the time of sacrifice, blood samples were collected for a biochemical analysis, followed by liver tissue collection for histopathological study. Results showed that BPS-induced hypertriglyceridemia, increased liver injury markers, and initiated histopathological changes, including inflammatory cell infiltration, hepatocellular necrosis, and steatosis. BPS did not affect glycated hemoglobin (HbA1C). Interestingly, data showed that BPS could interact with the PPARγ ligand-binding pocket by hydrogen bonds with Asn 219, Cys 276, Ser 280, and Thr 283. We suggest that PPARγ is among the targets of BPS and could play a key role in the cascade reaction of BPS-induced liver disruption. These findings support the hypothesis that the post-weaning period is sensitive to low-dose BPS exposure that can lead to dyslipidemia signature later in life.

Barangi, Samira; Asadi, Rouzchehr; Mehri, Soghra; Karimi, Gholamreza

doi: 10.1177/07482337231166491pmid: 37022282

Benzo(a)pyrene is a ubiquitous environmental contaminant, which could induce renal injury. It is reported that melatonin has a protective effect against multiple organ injuries by regulating oxidative stress, apoptosis, and autophagy. The aim of this study was to estimate the melatonin effects on benzo(a)pyrene renal toxicity in mice and the possible molecular mechanisms involved in this model. Thirty male mice were allocated to five groups and treated with benzo(a)pyrene (75 mg/kg, oral gavage) and/or melatonin (10 and 20 mg/kg, intraperitoneally). The oxidative stress factors were evaluated in renal tissue. The levels of apoptotic (the Bax/Bcl-2 ratio and caspase-3) and autophagic (the LC3 II/I, Beclin-1, and Sirt1) proteins were examined using Western blot. Following the administration of benzo(a)pyrene, malondialdehyde, caspase-3 and the Bax/Bcl-2 ratio increased in renal tissue, while Sirt1, Beclin-1, and the LC3 II/I ratio diminished. Interestingly, the co-administration of 20 mg/kg melatonin along with benzo(a)pyrene reduced the oxidative stress markers, apoptotic and autophagic proteins. Collectively, melatonin exhibited a protective effect against benzo(a)pyrene-induced renal injury through the suppression of oxidative stress and apoptosis and the inhibition of Sirt1/autophagy pathway.

Adedire, Chris O; Akinduro, Oluwayomi O; Adeyemi, Joseph A

doi: 10.1177/07482337231169091pmid: 37022338

Pesticides are routinely applied by cocoa farmers to enhance cocoa production, which is threatened by pest infestations and diseases. However, the undesired health implications of pesticide applications on the farmers are yet to be fully elucidated especially among cocoa farmers in Idanre despite being the hub of cocoa production in Southwestern Nigeria. This study assessed the extent of pesticide use by cocoa farmers in the study area and determined the effects of exposure on their health using haematological and biochemical parameters as indices. A cross-sectional survey comprising 150 cocoa farmers and 50 controls (artisans) was carried out using structured questionnaire. Blood samples were obtained from participants for the determination of copper and sulphate levels, haematological (haematocrit, red blood cell counts, white blood cell counts and platelet counts) and biochemical (creatinine, cholesterol, direct bilirubin and total bilirubin) parameters. The blood levels of copper and sulphate were significantly higher in the cocoa farmers than in the controls. However, there was no significant difference between the subjects and controls for most of the haematological and biochemical parameters except for the platelet counts and total bilirubin levels. The data from the study did not suggest any serious health effects due to pesticide exposure on the cocoa farmers despite the high blood levels of copper and sulphate, probably due to exposure to copper-based fungicides. However, the high serum bilirubin level among the subjects was an indication of possible liver damage. As such, cocoa farmers should be guided against indiscriminate use of pesticides on their farms.

Odewabi, Adesina O; Ajibola, Romoke S; Oritogun, Kolawole S; Ekor, Martins

doi: 10.1177/07482337231169085pmid: 37082971

Toxic pneumonitis and related respiratory symptoms are common among waste management workers (WMWs). Products of different cellular responses following exposure to toxic components of wastes can lead to the production of a variety of biomolecules. There is a growing recognition of the importance of biomarkers in risk assessment and a strong advocacy for their determination and use as indicators of health and safety. This study assessed the prevalence of respiratory symptoms and the relevance of pulmonary surfactant protein A (SP-A) and Clara cell 16 protein (CC16) as indicators of occupational inhalation exposure to toxic substances and irritants in WMW. A total of 172 subjects consisting of 112 WMWs and 60 Non-WMWs were recruited by purposive sampling. Data on socio-economic and work-related symptoms were collected using structured questionnaire. CC16 and SP-A were determined by ELISA in serum samples. Clinical history reveals a slightly higher prevalence of respiratory symptoms in WMWs relative to control subjects. Increased permeability of the lung–blood barrier, characterized by significant elevation of serum SP-A and serum CC16, was associated with respiratory symptoms in WMWs. Steady increases in SP-A and CC16, respectively, in relation to occupational duration were observed in WMWs relative to control. Receiver operating characteristic curve and multivariate analyses revealed SP-A and CC16 as important lung biomarkers for assessing sub-clinical effects of occupational exposure. Our data suggest SP-A and CC16 may be relevant indicators for assessing occupational inhalation exposure to toxic substances and irritants among WMWs.

Sweilum, Ola; El-Badry, Aziza; El-Agamy, Situhom

doi: 10.1177/07482337231171294pmid: 37073565

Lead shielding is used as a guard against scatter radiation. Lead aprons can emit particulate lead into the occupational environment, resulting in the accumulation of lead dust on the skin and garments of workers. This study aimed to assess the risk of lead exposure among radiologists working in the radiology departments by estimating hair and blood lead levels. A total of 40 radiology personnel (18 wearing aprons and 22 not wearing aprons) with a comparable control group (20 personnel not working in a radiology department) underwent a pre-designed questionnaire with estimation of blood and hair levels. The hair and blood lead levels in radiologists wearing aprons were significantly higher than those of the control group and that of the radiologist not wearing aprons. The lead levels in hair and blood were correlated significantly with the duration of wearing aprons in years and weekly working hours. Health care workers in radiology departments demonstrated high hair and blood levels that were higher among workers wearing aprons than those not wearing protective equipment. Hair lead levels can be detected quickly, cheaply, and non-invasively, and could be a helpful screening test for occupational exposure.