Occupational exposure to zoonotic agents among agricultural workers in Lombardy Region, northern Italy.

OBJECTIVES: This study was conducted in Northern Italy with the aim of defining the risk of agricultural workers' contact with biological agents through the determination of serum antibodies against selected zoonotic agents. Immunity against tetanus was also investigated. METHODS: Two groups of agricultural workers consisting of 153 animal breeders (exposed) and 46 non- breeders (controls) were included in the study. In a first group of 103 workers (89 exposed and 14 controls) the serum concentrations of antibodies against Hepatitis E Virus (HEV) were measured, whereas in the second group of 96 workers (64 exposed and 32 controls) the serum concentrations of antibodies against Leptospira spp., Coxiella burnetii, Borrelia burgdorferi, Brucella spp. and Salmonella spp. were addressed. Imunization against tretanus was also studied in this group. RESULTS: Animal breeders showed higher rates of IgG antibodies against Coxiella burnetii (50% vs. 31.2%), and Leptospira spp. (59.4% vs. 43.7%). Results of logistic regression analysis revealed that breeder workers showed a tendency to have higher prevalence of positivity for antibodies to Leptospira spp.and Coxiella burnetii than non-breeders (ORs ~ 3). Only one exposed subject showed antibodies against hepatitis E (none in controls), but when tested with another commercially available kit the percentage of anti HEV IgG positive subjects increased to 22.3% in the exposed, while none of the controls showed positive. None of the subjects showed antibodies against Salmonella spp. and Brucella spp. Italians and other European workers have better protection against tetanus (91%) compared to non-EU workers (81%). CONCLUSIONS: The higher frequency of the presence of serum antibodies to zoonotic agents (e.g. Leptospira spp. and Coxiella burnetii) in animal breeders suggests that they are more exposed to biological agents than workers not involved in animal breeding activities. The risk of contact with HEV deserves further studies because the adoption of different assays can result in significantly different results. The promotion of immunization of agricultural workers might be a priority, in particular for migrants.

Emerging zoonoses: the "one health approach".

Zoonoses represent a public health risk recently pointed out by the spreading of previously unknown human infectious diseases emerging from animal reservoirs such as severe acute respiratory syndrome and avian influenza caused by H5N1-virus. These outbreaks have shown that animal breeding activities can pose a significant public health risk. Until now, the risk of zoonoses has probably been underestimated, particularly in occupational settings. The emergence or re-emergence of bacterial (Mycobacterium bovis and Brucella spp) or viral (hepatitis E virus) infections shows that zoonoses should be considered as emerging risks in agricultural and animal breeding and should be addressed by specific preventive interventions. Close cooperation and interaction between veterinarians, occupational health physicians and public health operators is necessary, for a worldwide strategy to expand interdisciplinary collaborations and communications in all aspects of health care for humans, animals and the environment. This is what the One Health Approach was intended to be.

Immune changes in animal breeders: a pilot study conducted in northern Italy.

OBJECTIVE: Farming is associated with exposure to a wide variety of risk factors including organic dusts, endotoxins, allergens and other chemicals. The ability of some of these agents to interact with the immune system is demonstrated in the presented study which was undertaken to evaluate the relationship between pig and cow breeding, and the immune system early changes. Particular attention is paid to selected serum cytokines. METHODS: Sixty four animal breeders (36 cattle and 28 pig breeders) were selected as the exposed group, and 32 rural workers not engaged in animal breeding were utilised as the controls. Personal data were collected through a questionnaire, and selected serum parameters measured, including cytokines IL-6, IL-8, IL-10, IFNγ and TNFα, immunoglobulins and proteins, and total and differential white blood cell counts. RESULTS: The study stresses the significant increase of TNF-α, IL-8, and IL-10 in animal breeders, with the highest values in pig breeders, and a slight but statistically significant increase in albumin and total serum proteins. CONCLUSIONS: The findings of the presented study suggest a condition of immune system activation in animal breeders, with the highest levels observed in pig breeders. These changes may be attributable to exposure to organic dusts, endotoxins, or to the different biological agents present in the rural environment. The prognostic significance of these findings, however, remains unclear, but the observed changes might be indicative of a risk of developing respiratory toxic and allergic diseases, which need to be further investigated.

Farmers' exposure to herbicides in North Italy: assessment under real-life conditions in small-size rice and corn farms.

Although rice and corn are two main cash crops in Lombardy (North Italy) and their cultivation involves several thousands of farmers, risk assessment of pesticide exposure is rarely done, especially in small and medium sized enterprises. With the use of pads for environmental monitoring (OECD protocol), of pre- and post-exposure 24h urine collection for biological monitoring and of hand wash for hands' exposure, we measured the exposure of 28 agricultural workers to propanil and terbuthylazine in real-life working conditions. In propanil applicators, median daily exposure on the clothes was 73.5µmol per worker, while the exposure on the skin was 22.4µmol. For terbuthylazine, these exposures were 37.2µmol and 0.86µmol per worker, respectively. Median excretion of the propanil metabolite (3,4-dichloroaniline) after exposure was 84nmol in 24h urine, and 13nmol for the metabolite of terbuthylazine. Risk assessment performed by comparing to the AOELs of the applied active ingredients with an estimated internal dose, obtained based on the measured levels of skin and hand exposure and the percentage of dermal absorption of the active ingredients considered showed that 4 propanil workers, and no terbuthylazine workers, were overexposed. Our study helps define and confirm relationships between different exposure determinants, which can be used in the development of tools for risk assessment of exposure to pesticides in small and medium sized enterprises.

Integration of biological monitoring, environmental monitoring and computational modelling into the interpretation of pesticide exposure data: introduction to a proposed approach.

Open field, variability of climatic and working conditions, and the use of complex mixtures of pesticides makes biological and environmental monitoring in agriculture, and therefore risk assessment and management, very complicated. A need of pointing out alternative risk assessment approaches, not necessarily based on measures, but simple, user-friendly and reliable, feasible also in the less advanced situations and in particular in small size enterprises, arises. This aim can be reached through a combination of environmental monitoring, biological monitoring and computational modelling. We have used this combination of methods for the creation of "exposure and risk profiles" to be applied in specific exposure scenarios, and we have tested this approach on a sample of Italian rice and maize herbicide applicators. We have given specific "toxicity scores" to the different products used and we have identified, for each of the major working phases, that is mixing and loading, spraying, maintenance and cleaning of equipment, the main variables affecting exposure and inserted them into a simple algorithm, able to produce "exposure indices". Based on the combination of toxicity indices and exposure indices it is possible to obtain semiquantitative estimates of the risk levels experienced by the workers in the exposure scenarios considered. Results of operator exposure data collected under real-life conditions can be used to validate and refine the algorithms; moreover, the AOEL derived from pre-marketing studies can be combined to estimate tentative biological exposure limits for pesticides, useful to perform individual risk assessment based on technical surveys and on simple biological monitoring. A proof of principle example of this approach is the subject of this article.

A simple and fast method for the determination of selected organohalogenated compounds in serum samples from the general population.

Polychlorinated biphenyls (PCBs) and organochlorine pesticides (OCPs) have been widely used in industry and agriculture. Due to their persistence and bioaccumulation, they were globally spread in the environment and may still be found in environmental and biological media, despite the international restrictions on production and use. The main aim of our study was to develop a simple and fast method suitable for the establishment of the reference values for 15 PCB congeners and 16 OCPs in general population subgroups. A cost- and time-saving screening procedure using gas chromatography coupled with low-resolution mass spectrometry, was improved and validated before application to the analysis of real samples. The overall method was validated including uncertainty measurement. Preliminary field data were collected from 95 volunteers living in two Italian areas. HCB, p,p'-DDE, PCB 153, PCB 138 and PCB 180 were the most frequently detected compounds. Age and residence area were found to be significant variables for the most abundant compounds, while no correlation between serum concentrations and gender was observed. Our results suggest that long-banned substances, including PCBs and the pesticides HCB and DDT's breakdown product, are still detectable in the general population.

Results of the monitoring program of pesticide residues in organic food of plant origin in Lombardy (Italy).

Organic agriculture, with its restrictions on the use of synthetic chemical inputs, seems to offer a low-residue alternative to conventional methods. In Europe, the Council Regulation n. 2092/91/EEC regulates the production and trade of organic products and foodstuffs; national and regional legislation in Italy gives specific guidance on the surveillance of organic agriculture. However, monitoring of specific chemical residues in organic foodstuffs is part of the regular controls on food, aiming to safeguard consumer's health. Monitoring programs are coordinated at the national level by the Ministry of Health and at local level by Regional authorities. In Lombardy, in accordance with the provisions of the General Directorate of Health of the Region and under the supervision of the 15 Local Health Units, a monitoring program of pesticide residues in food of plant origin is undertaken every year. The International Centre for Pesticides and Health Risk Prevention (ICPS), on behalf of the General Directorate of Health of the Region of Lombardy, has been collecting and elaborating the data resulting from the analysis of food samples, carried out by the local laboratories. During the period 2002-2005, a total of 3508 samples food of plant origin were analyzed for pesticide residues, among which were 266 samples of organic farming products. Commodities were classified into groups (citrus fruits, legumes, vegetables, potatoes, processed products, cereals, and fruit other than citrus) and the outcomes of the analyses were reported by year, origin of the sample and presence/absence of pesticide residues. Results showed that the vast majority of organic farming products were in conformity with the relevant legislation and did not contain detectable pesticide residues. A limited amount of samples had residues at concentration below the Maximum Residue Limit (MRL). Only in one sample the residue level was above the MRL, however it did not pose a concern for public health, as demonstrated by the outcomes of dietary risk assessment. Organic fruits and vegetables can be expected to contain fewer agrochemical residues than conventionally grown alternatives. There is a widespread belief that organic agriculture products are safer and healthier than conventional foods. It is difficult to come to conclusions, but what should be made clear to the consumer is that "organic" does not automatically equal "safe". In the absence of adequate comparative data, additional studies in this area of research are required.

Antibiotic susceptibility of coagulase-negative staphylococci isolated from goats' milk.

The antibiotic susceptibility of 70 strains of coagulase-negative staphylococci (CNS) isolated during the 2001 lactating period from the milk of dairy goats, was evaluated. The antibiotics tested were benzylpenicillin, cloxacillin, amoxicillin, amoxicillin plus clavulanic acid, cephalonium and cefoperazone, erythromycin and tylmicosin, kanamycin and tetracycline. Minimum inhibitory concentration (MIC) measurements showed that all beta-lactams (except cefoperazone) were effective against Staphylococcus epidermidis and Staphylococcus caprae, whereas the other antibiotics were either less effective or showed no activity. Other CNS species showed very variable sensitivity to the antibiotics; testing would be required before therapy for the clinical control of goat mammary infections.