Toxicology and Industrial Health

Azadi, Mahak; Hasani, Amir Hessam; Olya, Mohammad Ebrahim; Borghei, Seyed Mehdi

doi: 10.1177/0748233718796720pmid: 30453841

In the present research, a zinc oxide (ZnO)–silver (Ag)–neodymium (Nd) nanocomposite was synthesized via the combustion method for the degradation of dyes as organic pollutants. The synthesized nanophotocatalyst was characterized using X-ray diffraction, Fourier transform infrared spectroscopy, and scanning electron microscopy techniques. The process of organic pollutant (Acid Red 18) removal was carried out in a semi-batch photoreactor equipped with an ultraviolet lamp. Also, the influence of key operational parameters such as pH, temperature, initial concentration of solution, and nanophotocatalyst dosage was investigated to evaluate kinetic and thermodynamic properties. Under optimum process conditions (pH = 6.21, dosage of nanophotocatalyst = 0.08 g/l, and low initial concentration of the solution), degradation of pollutant was monitored by measuring the total organic carbon of the solution. Finally, an economic study showed that the photocatalytic advanced oxidation process is an viable treatment method for low concentrations of organic pollutants.

Shabnam, Kuder Reshma; Gangappa, Dharmapuri; Philip, Gundala Harold

doi: 10.1177/0748233718807046pmid: 30518298

Evaluation of the toxic effects of a widely used synthetic pyrethroid, deltamethrin (DM), was carried out in this study. This pesticide is preferred for pest control because of its low environmental persistence and toxicity. We investigated the expression pattern of four genes, namely, you (you), yot (you-too), momo (mom) and ubo (u-boot) during early development of zebrafish, that is, from 12 hpf to 48 hpf stages. These stages are selected as most of the important developmental aspects take place during this period. All four genes are known to play a vital role in development of notochord and somites. To understand the effect of DM on development, embryos of 4 hpf stage were exposed to two concentrations (100 and 200 µg/L) of DM, and observations were made at 12, 24 and 48 hpf stages. Our earlier studies have shown phenotypic abnormalities such as notochord bending, tail deformation, yolk sac and pericardial edema, lightening of body and eye pigmentation and interfered in somite patterning, during these stages of development. Understanding the relationship of phenotypic abnormalities with these four genes has been our primary objective. These four genes were analyzed by Reverse transcription (RT)-polymerase chain reaction and intensity of the bands has shown induction in their expression after exposure to the toxicant. In spite of the expression of genes, it was noticed that DM caused abnormalities. It can be said from the results that translational pathway could have been affected.

Yu, Jimian; Wang, Wei; Wang, Jianfeng; Wang, Chun; Li, Caiyan

doi: 10.1177/0748233718807303pmid: 30453839

The objective of this study was to investigate changes in intestinal histopathology and expression of heat-shock proteins (HSPs) in the small intestinal tissue of mouse after acute exposure to dibutyl phthalate (DBP). Forty-eight 60-day-old Institute of Cancer Research (ICR) mice were administered DBP by gavage once a day for 10 days. The mice were divided into three groups of 16 mice each: the high-dose group was administered 500 mg/kg body weight (BW) DBP; the low-dose group was administered 50 mg/kg BW; and the control group was not administered DBP. Significant increases in the uterine index, ovary index, and testicular index were observed in the DBP-exposed groups compared to those in the control group. Villus height and V/C ratio significantly increased (p < 0.05) in the duodenum and decreased (p < 0.05) in the jejunum after the administration of DBP. The goblet cell number decreased in both the duodenum and the jejunum of mice exposed to DBP (p < 0.05) compared to the number in the control group mice. Damage to the structure of the small intestine was accompanied by a marked increase in HSP27 expression and a decrease in the expression of HSP70 and HSP90 in both high-dose and low-dose groups. These results indicate that elevated HSP27 levels in the duodenum and jejunum may be important markers for acute DBP exposure and that HSP27 may act as a protective protein involved in intestinal mucosa repair.

Hormozi, Maryam; Mirzaei, Ramazan; Nakhaee, Alireza; payandeh, Abolfazl; Izadi, Shahrokh; Haghighi, Javid Dehghan

doi: 10.1177/0748233718809256pmid: 30453844

Recently, there is a growing interest for the use of antioxidants as a preventive agent against cadmium (Cd) intoxication. The current study aimed to investigate the effects of dietary coenzyme Q10 supplementation on oxidative stress and antioxidant enzymes activity in Cd-exposed glazers. In a randomized, double-blind, placebo-controlled 2-month crossover clinical trial, coenzyme Q10 (60 mg twice daily) or placebo was administrated to 40 male glazers occupationally exposed to Cd. The subjects were randomly assigned to the placebo and coenzyme Q10 groups (n = 20 in each group). Total antioxidant capacity (TAC), superoxide dismutase (SOD), glutathione peroxidase (GPx), and catalase (CAT) as well as malondialdehyde (MDA) in the serum of glazers were measured at baseline and at the end of both intervention phases. The primary outcomes were the changes in serum levels of MDA, TAC and the activities of SOD, CAT, and GPx during administration with coenzyme Q10 versus placebo. Compared with placebo, treatment to coenzyme Q10 was associated with a significant reduction in serum MDA levels (p < 0.001) While, there was no significant effect on the serum TAC levels (p = 0.096). Also, the activity antioxidant enzymes of SOD (p < 0.001) and GPx (p = 0.003) were significantly higher and the CAT activity (p < 0.001) was lower after 2-month coenzyme Q10 administration compared with placebo. Data demonstrated that coenzyme Q10 supplementation at a dose of 60 mg (twice daily) is effective in reducing oxidative stress marker level (MDA) and improving antioxidant enzymes activity in glazers exposed to Cd. However, further research is needed to assess coenzyme Q10 as a possible dietary intervention in Cd-exposed workers.Trial Registration:Iranian Registry of Clinical Trials Registration Number: IRCT2016061228407N1 (www.who.int/ictrp/network/irct/en/).

Yang, Haibo; Wang, Jifeng; Yang, Xinxin; Wu, Fengdi; Qi, Zhipeng; Xu, Bin; Liu, Wei; Deng, Yu

doi: 10.1177/0748233718810109pmid: 30466360

It has been found that exposure to manganese (Mn) could induce reproductive dysfunction, but its occupational risk in male workers is unclear. This study aims to assess the association of occupational Mn exposure with reproductive hormones and semen quality in a cross-sectional study. Urinary Mn, semen quality, and reproductive hormones were explored in 84 male workers occupationally exposed to Mn and 92 referents. Multiple linear regression analyses were used to assess the relationship. Urinary Mn levels in Mn-exposed workers ranged from 0.56 to 34.25 µg/L, and the average level was 15.92 ± 8.49 µg/L. Compared with the control group, gonadotropin-releasing hormone (GnRH) levels and luteinizing hormone (LH) levels increased significantly and the levels of testosterone (TSTO) decreased significantly in the Mn-exposed group. There was a significant positive linear association between urinary Mn and GnRH and LH, while the linear association between urinary Mn and TSTO was negative. Sperm progressive motility and total motility decreased significantly in the Mn-exposed group. There was a significantly negative linear association between urinary Mn and sperm progressive motility and total motility. In conclusion, occupational Mn exposure was inversely associated with reproductive health of male workers, resulting in the abnormality of hormones secretion and decrease of sperm motility.

Allam, Ahmed A; Othman, Sarah I; Mahmoud, Ayman M

doi: 10.1177/0748233718814971pmid: 30803421

The present study aimed to investigate the impact of perinatal potassium bromate (KBrO3) exposure on the development of sensorimotor reflexes and redox status, and on the histological architecture of the brain, liver, and kidney of newborn mice. Pregnant mice received 1-ml bottled drinking water daily by oral intubation and served as the control group. Another group of pregnant mice were supplemented orally with 200 mg/kg body weight KBrO3 dissolved in drinking water from gestation day 5 to postnatal day 21. KBrO3 induced a decrease in the postnatal body weight in the newborn mice. KBrO3-exposed newborn mice showed poor performance and delayed development of the sensorimotor reflexes. Histological changes, increased lipid peroxidation, and altered antioxidants were reported in the cerebrum, cerebellum, medulla oblongata, liver, and kidney of the KBrO3-exposed newborn mice. In conclusion, these findings demonstrated that perinatal exposure to bromate induced oxidative stress, histological and behavioral alterations, and was a potential teratogen in newborn mice.

Nasirzadeh, Nafiseh; Azari, Mansur Rezazadeh; Rasoulzadeh, Yahya; Mohammadian, Yousef

doi: 10.1177/0748233718817180pmid: 30803420

Nanomaterials are widely used nowadays in a range of technological and biomedical fields. Graphene as a nanomaterial used in the health-care sector and in workplaces has raised some concerns about its toxicity. This study aimed to evaluate the cytotoxicity of graphene nanoparticles (GNPs) on the A549 epithelial cells of the human lung. The GNPs were synthesized from graphite by the modified Hummer method. The physicochemical characteristics of GNPs were identified by the transmission electron microscope, the scanning electron microscope, and the Brunauer–Emmett–Teller method. The hydrodynamic size of GNPs in the dispersion media was examined using the dynamic light scattering technique. The GNPs were dispersed, after which the A549 cells were cultured. Finally, the cell viability was assayed by the MTT assay. The statistical analysis of variance was used to describe the relationship between the concentration/time variables and the GNP-induced cell deaths. The probit regression model was also used to achieve toxicological indicators. The results showed that the toxicological effects of GNPs on the A549 epithelial cells of the human lung are dose- and time-dependent. The GNPs were more cytotoxic after a 72-h exposure period compared to a 24-h and 48-h exposure period. The inhibitory concentration of 50% and “no observed adverse effect concentration” were estimated to be 40,653.1 and 0.059 µg/mL, respectively. The results of this study can be helpful in developing the occupational exposure limit for GNPs and in improving occupational health programs in workplaces. However, more investigation is needed to specify the toxicological mechanisms of GNPs.