Formaldehyde is a chemical which is traditionally used as disinfectant and preservative. Recently,formaldehyde becomes raw material of adhesive which is widely used for indoor decoration. It has been recently reported in many animal experiments that formaldehyde had adverse effects on male reproductive endocrine,sperm quantity and quality,and but few reports were obtained about the adverse effects of formaldehyde on male reproductive system in human beings. Damage to genetic material,induced by lipid peroxidation and cell apoptosis is the possible mechanism of toxic effect. Male reproductive toxicity and mechanism of formaldehyde were discussed,and the recent researches were reviewed in the present paper.

Objective To understand the sanitary status of the air conditioning system of public places and to discuss the countermeasure.Methods Fifty public places where the air conditioning system were used were selected as the research objects in September 2008.The questionnaires about the hygienic management, the air conditioning system and the cooling tower were used to investigate the basic situations of the air conditioning system in public places,and Legionella pneumophila(Lp) of cooling water in the cooling tower was detected.Results All the fifty public places didn't establish complete sanitary management system.90% of the cooling towers were less than one kilometer from the residential areas, schools, kindergartens, agedness flats and hospitals.And 18% of the cooling towers were less than one hundred meters from the walking streets and entertainment plaza.Moreover,8% of the public places had not fresh air, the air purification wasn't installed in 74% of the public places and sterilization equipments, and automatic or on-line sterilization equipments in the cooling towers weren't installed in all the public places.In addition, the positive rate of Legionella pneumophila in the cooling towers was 89.58%.Thereinto, the positive rate of Lp1 type(79.07%) of Legionella pneumophila was significantly higher than that of Lp2-Lp14 type(11.63%) as well as that of Lp1 type and Lp2-Lp14 type(9.30%)(P0.05).Conclusion The air conditioning systems of public places are being faced with some sanitary problems and the cooling water in the cooling tower was polluted with Legionella pneumophila.Therefore,it is suggested that its sanitary management should be reinforced and the sterilization management of cooling water as well as the shield between the cooling towers and the circumferences should be taken into account.

Objective To understand and analyze the epidemiological and pathogenic characteristics of foodborne diseases in Changzhou in the past five years, so as to provide evidence for prevention and control measures. Methods All foodborne disease surveillance information reported by Changzhou foodborne disease sentinel hospital from 2016 to 2020 was collected through the ^“Foodborne Disease Surveillance and Reporting System^”. The distribution of reported cases and etiological results was described, and the possible factors affecting pathogen detection results were analyzed. Results A total of 14 931 cases of foodborne diseases were reported, mainly distributed in summer and autumn, and peaked in July and August. The age group of reported cases was 25-34 years old, and the occupations were mainly workers, and farmers and migrant workers, accounting for 23.2% and 36.9%, respectively. Among the reported cases of 3 120 anal swabs were collected and tested for etiology , of which 291 specimens were positive, with a positive detection rate of 9.32%. Among the 291 positive results of 118 cases of norovirus were detected, with a detection rate of 6.03% . 66 cases of salmonella were detected, with a detection rate of 2.12% . 25 cases of vibrio parahaemolyticus were detected, with a detection rate of 0.80% . 7 cases of diarrhea-causing Escherichia coli was detected, with a detection rate of 0.22% ; and 5 cases of shigella was detected, with a detection rate of 0.16% . Single factor analysis of the results of pathogen detection showed that there were no statistical differences in the distribution of positive pathogen detection rate between males and females, and between different suspicious exposed foods (all P>0.05). There were statistical differences in different age groups, occupations, seasons and eating places (all P<0.05). Multivariate Logistic regression analysis showed that age and season were correlated with the detection rates of pathogenic microorganisms (all P<0.05) , and age was negatively correlated with the positive rate of pathogenic microorganisms (OR=0.863). The detection rates in the first and fourth quarters were higher than those in the second and third quarters. Conclusion Summer and autumn are the seasons with high incidence of foodborne diseases in Changzhou. Norovirus is the main pathogen. Age and season are closely related to the detection results of pathogenic microorganisms. Comprehensive prevention and control measures should be implemented for key population in summer and autumn to reduce the occurrence and outbreak of foodborne diseases.