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Presented research concerns the evaluation of residues of chemical pesticides in crops, depending on the system and production sites. The study was conducted in 2005–2008 on 618 samples from conventional system and 320 from integrated system of plant material derived from the four voivodeships: Lubelskie, Podlaskie, Warmia-Mazury and Mazowsze. On the basis of the studies it was shown that the crops produced in the integrated system contained a larger percentage of samples with residues below the maximum levels compared to samples from conventional and less with above MRL. The percentage of samples from the border limits for Lubelskie and Podlaskie was equal to 4%, Warmia and Mazury 2% in Mazowieckie, there was no such irregularities.
Pesticide poisoning of honey bees can be a serious problem. Honey bees provide a valuable service to agriculture because they are known as the most important pollinators of cultivated crops. Efforts should be made to protect honey bees whenever pesticides are used. The analyses of samples of poisoned bees revealed that the most common cause of poisoning of bees were pyrethroids, organophosphorus insecticides. Ignoring the safety precautions included in the label of plant protection products as well as unauthorized use of pesticides led to mortality of numerous honeybees families. Moreover, the use of biocides recommended by some specialized companies for harmful insect regulating such as mosquitoes caused bee poisoning on large scale. LD50 calculated for bees poisoned by biocides was dozen to several thousand times higher as compared to LD50 for bees poisoned by plant protection products. The protection of honeybees has become even more critical in recent years.
Fruit and vegetables are a valuable and essential component of a human diet. Unfortunately, the widespread and increasingly popular use of pesticides has largely magnified quantities of pesticide residues in these plant products. Among the best methods for removal of these contaminants from food of plant origin are food processing technologies, which affect the levels of pesticide residues to various degrees. The aim of this study was to compare the effects of different water and thermal processing treatments on pesticide residue concentrations in selected fruit and vegetables obtained from controlled field and tunnel trials. Black currants, broccoli, strawberries and tomatoes sprayed with plant protection products were analyzed. Washing by immersion in chlorine and in ozonated water as well as boiling were used to assess the removal of eleven pesticides in blackcurrants, broccoli, strawberries and tomatoes. Processing factors, which were determined for each combination of a pesticide, commodity and processing method, ranged between 0.03 and 1.66. Washing in ozonated water was more effective than washing in chlorinated water. However, high temperature at boiling caused a significant decrease in the concentration of most compounds (up to 97%), although there were some exceptions. The thermal treatment proved to be the most effective technological process removing pesticide residues from different commodities. The water and thermal processing technologgies tested in this experiment are promising methods for fast and simple removal of pesticide residues from broccoli, black currants, strawberries, tomatoes and possibly other commodities.
In the years 2008-2010, 64 samples of plant material derived from farms in the north-eastern Poland were tested towards proper application of plant protection products (PPP) and food safety. It was found that 28% of pesticide treatments were carried out against recommendations of pesticide producers. The average consumption of pesticides, calculated in kg of active substance·ha-1, ranged from 0.12-2.57. The costs of conducted treatments based on the prices of PPPs ranged from 67-574 PLN·ha-1. Cultivation of winter rape was characterized by the highest level of pesticide use and the highest price of treatments. In the tested samples no risk of pesticide residues to human and animal health was found.
The aim of performed questionnaire survey was to collect the information of plant protection products used in agricultural crops in the region of Suwałki. 42% of respondents confirmed the use of insecticides on their crops with the similar mechanism of action, herbicides were used by 30%, fungicides 28%. The high efficiency of the chemical method used to against agrophages in their own farm, confirmed by 80%, no improvement was observed by 12%, while 8% did not analyzed the results. In the majority of agricultural farms the most common weed was windgrass (Apera spica-venti), and pest as Colorado potato beetle, Cereal leaf beetles (Oulema spp.) and aphids occurred with the highest frequency amount insects. The most common cereal diseases were powdery mildew and rust.
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