Estimation of Smoking Index for Male Smokers in Multan City

Significant accumulation of persistent organic pollutants and dysregulation in multiple DNA damage repair pathways in the electronic-waste-exposed populations

Electronic waste (e-waste) has created a worldwide environmental and health problem, by generating a diverse group of hazardous compounds such as persistent organic pollutants (POPs). Our previous studies demonstrated that populations from e-waste exposed region have a significantly higher level of chromosomal aberrancy and incidence of DNA damage. In this study, we further demonstrated that various POPs persisted at a significantly higher concentration in the exposed group than those in the unexposed group. The level of reactive oxygen species and micronucleus rate were also significantly elevated in the exposed group. RNA sequencing analysis revealed 31 genes in DNA damage responses and repair pathways that were differentially expressed between the two groups (Log2 ratio >1 or <-1). Our data demonstrated that both females and males of the exposed group have activated a series of DNA damage response genes; however many important DNA repair pathways have been dysregulated. Expressions of NEIL1/3 and RPA3, which are critical in initiating base pair and nucleotide excision repairs respectively, have been downregulated in both females and males of the exposed group. In contrast, expression of RNF8, an E3 ligase involved in an error prone non-homologous end joining repair for DNA double strand break, was upregulated in both genders of the exposed group. The other genes appeared to be differentially expressed only when the males or females of the two groups were compared respectively. Importantly, the expression of cell cycle regulatory gene CDC25A that has been implicated in multiple kinds of malignant transformation was significantly upregulated among the exposed males while downregulated among the exposed females. In conclusion, our studies have demonstrated significant correlations between e-waste disposing and POPs accumulation, DNA lesions and dysregulation of multiple DNA damage repair mechanisms in the residents of the e-waste exposed region.

Carcinogenic effects of aflatoxin B1 among wheat handlers

BACKGROUND

Epidemiological studies have demonstrated that serum aflatoxin B1 (AFB1) is a hepatocarcinogenic mycotoxin and contributor to the high rate of hepatocellular carcinoma (HCC). The prevalence of liver cancer in Egypt is particularly worrisome. In a registry-based analysis of occupational risk for HCC, significant excesses were observed especially for grain mill workers.

OBJECTIVE

The aim of this study was to assess the hepatic carcinogenicity of AFB1 in wheat handlers.

METHODS

Serum AFB1/albumin (AFB1/Alb), alpha-fetoprotein (AFP), alpha-l-fucosidase (AFU), and arginase were estimated in exposed wheat handlers including millers and bakers. The control group was composed of non-occupationally exposed workers.

RESULTS

AFB1/Alb and AFU were significantly higher among workers employed as bakers compared to mill workers and controls. Mill workers had higher levels of AFB1/Alb than the controls. AFB1/Alb, AFP, and AFU were all significantly higher and arginase was significantly lower among HCC cases compared to the other groups. There was a significant correlation between AFU and AFB1/Alb in bakers and between AFP and AFB1/Alb in HCC cases. Arginase was inversely correlated with AFB1/Alb in HCC cases. AFB1/Alb was significantly correlated with the duration of exposure in bakers.

CONCLUSION

Wheat handlers exposed to Aspergillus flavus have a high risk of elevated serum AFB1/Alb levels and AFU.

Impact of aluminum exposure on lung

Aluminum (Al) metal is considered one of the most benign industrial metals. Although the harmful effects of Al on respiratory health have been denied by some studies, others reported its noxious effect on the lung through spirometric measurements. This work aimed at studying the effect of Al fumes on pulmonary functions of occupationally exposed workers. It investigated the possible relationship between inhalation exposure to Al fumes and levels of C-reactive protein (CRP) and alpha-1-antitrypsin (A1AT). The study participants comprised a group of 56 male Al workers with a mean duration of occupational exposure of 10.1 ± 9.5 years and 52 male participants who were not exposed to Al fumes as the control group. All participants filled a questionnaire, underwent full clinical examination and their spirometric pulmonary functions were measured. Blood samples were collected for the determination of serum CRP and A1AT and urine samples for measuring Al. Results revealed that urinary Al (UAl) was significantly higher in Al workers compared with controls (p < 0.05). However, spirometric measures showed no significant difference between the exposed group and the controls. A1AT was significantly lowered in Al workers compared with the controls (p < 0.000). Serum CRP was positive in only two (3.6%) of the exposed workers. Smokers of both groups (exposed and controls) showed significantly higher UAl and lower A1AT compared with nonsmokers. There was only significant negative correlation between the duration of exposure and A1AT (p < 0.05). There was a positive significant correlation between smoking index (SI) and UAl. There was also significant negative correlation between SI and some of the pulmonary function tests namely the percentage of predicted forced vital capacity, forced expiratory volume in the first second and peak expiratory flow in the exposed group. Those correlations point to the importance of the combined effect of smoking and Al exposure on the impairment of lung functions. The study recommends the determination of CRP and A1AT in Al-exposed workers. It is expected that those parameters may undergo changes before reduction in pulmonary functions takes place.

Serum bile acid as a screening tool in workers occupationally exposed to mixtures of organic solvents

The aim of the present study was to find out the potential impact of occupational exposure to mixtures of organic solvents on liver function tests. Serum bile acid (BA) was evaluated as a marker of early hepatic derangement and compared to routine liver function tests. The study included two comparable groups: 57 male workers exposed to organic solvents from a paints factory and 59 administrative male controls. Occupational and medical data and serum analysis for liver function parameters (BAs, alanine aminotransferase (ALT), aspartate aminotransferase (AST), gamma-glutamyl transpeptidase (GGT), alkaline phosphatase (ALP), total and direct bilirubin) were obtained. Bile acids showed significantly elevated mean levels in the exposed workers compared to the controls (50.2 ± 47.9 and 5.4 ± 2.7 µmol/L, respectively, p < 0.01). Bile acids were elevated in almost all exposed workers (87.7%) but in none of the controls. Bile acids had significant positive correlation with duration of exposure to organic solvents and lifetime hydrocarbon exposure score (HES) ( p < 0.01 and p < 0.05, respectively). All other liver function tests exhibited normal mean levels and did not show statistically significant differences between both groups. The performance of BA versus combined liver enzymes is evaluated using receiver–operating characteristic (ROC) curve and likelihood ratios. The area under the curve was significantly high (0.687 > 0.5, p = 0.012) and had optimal decision level (8 µmol/L). Serum BA can be recommended as a screening test for exposure to organic solvents. It can be suggested for follow-up every 1–2 years or accordingly.