Introduction: Controlling the presence of contaminants or harmful substances in milk and dairy products provides early detection of risks since their presence, even in legally permitted concentration, increases the risk of damaging human health, especially children's health, such as allergic manifestations, and they can have potentially toxic, carcinogenic and genotoxic effects. Aim of the Study: The aim is to determine the frequency of the presence of contaminants in samples of milk and dairy products in the Republic of Srpska from 2010 to 2012 (metals, radionuclides, aflatoxins and residues of antibiotics and pesticides), and especially to point out their public health significance because of possible health risks. The aim of the paper is to emphasize the need for monitoring all the other contaminants in milk and dairy products specified in regulations. Material and Methods: The frequency of the presence of contaminants in the samples of milk and dairy products (n= 407) was determined on the basis of legally prescribed methodology of sampling, chemical analyses and preparation of expert opinion on food safety in accordance with current food regulations. Descriptive statistical indicators were used (a number of the samples, minimum and maximum concentrations). Chi square test (χ2) of contingency was used for testing the significance of differences in presence of contaminants and residues analyzed and recommended by regulations in samples of milk and dairy products. Results: The results of public health research of contaminants in samples of milk and dairy products indicate that no health defective food samples were determined at tested parameters - metals, radionuclides, aflatoxins, and residues of antibiotics and pesticides. A statistically significant number of samples examined on heavy metal content (83.29% or 339 samples) was determined comparing to the number of samples examined on the other contaminants and residues recommended by regulations in milk and dairy products (χ2=1000.776, p<0.001) Conclusion: The data obtained can serve as a basis for further analysis in the context of milk and dairy product sample monitoring. Although samples of milk and dairy products are safe, a long-term exposure to residues of harmful substances results in cumulative effect and damage health, meaning that each early detection of food risk found through continuous controls has a public health significance for preservation and promotion of population health in the Republic of Srpska.

Introduction: Sex workers (SW) represent the population exposed to extremely high risk of HIV (HIV Human Immunodeficiency Virus) and other sexually transmitted infections. Poor socioeconomic conditions in the country, insufficient education, high unemployment and other factors lead to an increase in prostitution, which represents a high risk for the spread of HIV and other sexually transmitted diseases. Aim of the study: The aim of this research was to evaluate the prevalence of HIV/ sexually transmitted infections among SW in Bosnia and Herzegovina as well as to examine knowledge, attitudes and behaviour relating to HIV/sexually transmitted infections. The results were compared with the results obtained in researches conducted in 2008 and 2010. Material and Methods: Research was performed in 2012 as a bio-behavioral study that covered 199 sex workers in five cities of Bosnia and Herzegovina. Interviewing was done voluntarily, anonymously and confidentially, and after informed consent and councelling, a biological material (blood) for laboratory testing on HIV, hepatitis b, hepatitis c and syphilis was taken. The research shows the presence of risk behaviour among SW, mostly related to frequent change of partners and frequent unprotected sexual intercourses. Results: Only one third of respondents (36,7%) use condom during every sexual intercourse with a client, and 13% use it with a steady partner.A sexual intercourse after effects of consumption of alcohol-87,9% of respondents and of drugs-36,7% of respondents. Although there is a risk behaviour, only 11,1% think that the risk of HIV/sexually transmitted infections is high, but 12,6% think that there is no risk. Sex workers are 13,5 times more exposed to HIV infection than all the other women aged 1549. Results of laboratory testing indicate a low level of HIV/sexually transmitted infections among sex workers in Bosnia and Herzegovina. Conclusion: Although there is a relative progress in prevention of HIV/sexually transmitted infections among sex workers and more frequent testing on HIV/sexually transmitted infections comparing to earlier periods, these things are insufficient for the maintenance of a low level of infection. Further research at certain time intervals among this population would enable monitoring time trends of HIV epidemic in Bosnia and Herzegovina and would become a basis for the development of preventable programmes.