Journal of School of Public Health and

Hearing loss is a controversial occupational disease in fire fighters because exposure to hazardous levels of noise in this job is so variable and unpredictable. In this study, audiometric assessments were performed on 117 fire fighters to evaluate their hearing loss. The results showed that the average fire fighter has a characteristic noise-induced threshold shift, with maximum hearing loss occurring at 6000 Hz. The hearing loss at the test frequencies was related to age, although the association exceeded that of general population only in 6000 Hz frequency in left ear (p=0.021). Despite finding a pattern of threshold shift typical of occupational hearing loss, it must be noted that after controlling for age, there was no strong relation between length of time on the job and the degree of hearing loss. It seems that more extensive studies are needed to evaluate this relationship.

Background and Aim:  One of the biggest problems faced by parents of handicapped children is the child's health care. This study investigates patterns of heath care utilization and the related factors in children with mental impairment.

Material and Methods: This cross-sectional study involved 110 children (≤14 year old) with developmental disabilities in Tehran. Parents were selected by systematic random sampling for face-to-face interview.  Statistical analysis was based on negative binomial regression.

Results: Over 99% of the surveyed children received ambulatory care and 15 % had been hospitalized over the preceding year 0.9% had never used health services. These children had utilized health services 207+18 times in a year. Among these services 38+3 were not subsidized by the State. Factors affecting service utilization were parent information (p<0.033) and referral to the proper service delivery points (p<0.029).

Conclusion: Appropriate interventions are required to address the above-mentioned factors and improve service utilization.

  Background and Aim: Exposure to heavy metals always causes serious health problems in people working in the industry. Heavy metals may interfere with enzyme functioning or accumulate in specific body organs, leading to various health problems. Cadmium is a toxic heavy metal widely used in various industries and, therefore, workers in metal industries are at risk of exposure to it.

  Materials and Methods: A solid-phase sorbent was synthesized and factors influencing its sorption and elution steps were optimized (R>95%). The validated sorbent (chemically, physically and as regards reproducibility) was used to determine the cadmium content of the worker`s urines.

  Results: Optimized conditions for sorption and elution step were found to be as follows: pH= 7 sorption and elution time (both)= 5 min elution volume= 6 mL, and elution concentration= 2 mol L^-1. The great selectivity and the nano-particle size of the sorbent resulted in its highly precise performance (0.6ppb) and high validity and accuracy (CV<3%).

  Conclusion: Using the nano-magnetic sorbent technique and some such laboratory methods as flame atomic absorption spectroscopy, one can easily measure trace amounts of heavy metals in urine. This technique is relatively less expensive and rapid since, when using it, one can omit the filtration and centrifugation steps.

  Background and Aim: A ssociations between air pollution and morbidity have been reported in several studies. Due to limited publications in the literature for Iran, this study aimed to determine the association between air pollution and hospital admissions of respiratory disease patients in Tabriz, Iran.

  Materials and Methods: The methodology used in this study was case -crossover and the artificial neural network model. The variables of the model included air quality, hospital admission and air pollutants. Daily hospital admission data were collected from five hospitals in Tabriz, Iran based on the International Classification of Diseases (ICD-10) , air quality data including NO₂, SO₂, CO, PM₁₀ and O₃ from the six fixed online air quality monitoring stations, and the daily mean temperature and relative humidity data for the same period from the East Azerbaijan Meteorological Bureau.

  Results : P articulate matter with a median aerometric diameter <10 μm (PM₁₀) was found to be the most important pollutant affecting respiratory hospital admissions. The ANNs data showed that the most important causes of hospital admissions were for COPD NO₂, NO and CO, for respiratory infections PM_10, and for asthma PM₁₀, O₃ and CO. The highest associations were observed between hospital admissions due to COPD and asthma in females and those due to respiratory infections in males. The elderly (individuals over 65 years old) were at the highest risk.

  Conclusion: The results show a significant relation between air pollutants and respiratory hospital admissions in Tabriz, Iran. The importance and necessity of enforcement of existing regulations and enacting laws to prevent and control the adverse health effects of air pollution are confirmed.