Prevalence of upper limb musculo skeletal disorders among brass metal workers in West Bengal, India

Brass metal work is one of the oldest cottage industries in West Bengal, India. Workers performing rigorous hand intensive jobs are likely to suffer from MSD affecting the upper limbs. The present investigation was intended to establish the prevalence of upper limb MSD among the brass metal workers and to identify the causative factors behind its development. In this study, 50 male brass metal workers (Experimental Group) and 50 male office workers (Comparison Group) were selected. For the symptom survey, a questionnaire on discomfort symptoms was performed. Repetitiveness of work and Hand Grip Strength of both the groups were measured. It was revealed that upper limb MSD was a major problem among brass metal workers, primarily involving the hand, wrist, fingers and shoulder. Among the workers reporting subjective discomfort, most of them felt pain, followed by tingling and numbness in their hands. Many complained of swelling, warmth and tenderness in their wrists. Their activities were highly repetitive and the handgrip strength of these workers was significantly less than that of the comparison group. Based on these findings, it appears that high repetitiveness, prolonged work activity (10.5 h of work per day with 8.4 h spent on hammering) and decreased handgrip strength may be causative factors in the occurrence of upper limb MSD among brass metal workers in West Bengal, India.     

Dermal toxicity and microscopic alterations by JP-8 jet fuel components in vivo in rabbit

In this study, we investigated the skin irritation, macroscopic and microscopic barrier alteration in vivo in rabbits from aliphatic and aromatic components of jet propellant-8 (JP-8) jet fuel. Macroscopic barrier properties were evaluated by measuring transepidermal water loss (TEWL), skin capacitance, and skin temperature; microscopic changes were observed by light microscopy. Draize visual scoring system was used to measure skin irritation. We found significant (P<0.05) increase in temperature at the site of all chemically saturated patches immediately after patch removal in comparison to the control site. Tridecane (TRI) produced a greater increase in temperature and capacitance at all time points than all the other components of JP-8. Both the aliphatic and aromatic components increased the TEWL at all time points. Tridecane produced greater increase in TEWL followed by naphthalene (NAP), 1-methylnaphthalene (1-MN), 2-metylnaphthalene (2-MN), tetradecane (TET), and dodecane (DOD). All of the above components of JP-8 caused moderate to severe erythema and edema, which were not resolved to the baseline even after 24 h of patch removal. Light microscopy revealed an increase in epidermal thickness (ET), and decrease in length and thickness of collagen fibers’ bundle by the above components of JP-8. These results suggest potential dermatotoxicity from the JP-8 components.