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The wide-spread presence of silica in nature and the variety of materials containing it cause crystalline silica exposure of workers in various industrial activities. Moreover crystalline silica is classified as carcinogenic to humans (Group 1) by IARC, in relation to its possible lung carcinogenicity.The purpose of this paper was to assess respirable particles and crystalline silica exposure of workers in a number of some building sites located in the area of a Local Health Unit in the Umbria region. The study examined differences in four types of building sites: "construction of new buildings", "renovation of old buildings", "road construction" and "transport of aggregates by loaders in crushing plants". According to the strategy suggested by European Standard EN 689/1997, personal air samples were collected during work in jobs characterized by elevated amounts of widespread dust.Analysis of data showed that levels of exposure to crystalline silica were lower than the limits recommended by ACGIH/2010 in almost all samples except one. The percentages of crystalline silica in respirable particles were in the range 0.4%-21%. Crystalline silica exposure levels were different in the various jobs and comparison between the mean values of exposure levels in each one showed statistically significant differences (p0.01, variance analysis). Work with the highest exposure to crystalline silica were: brick cutting, plaster brushing, "Serena stone" cutting, as they use tools operating at high speed and often in dry conditions (grinder, power drill, pneumatic hammer), producing low-size airborne particles (respirable fraction). During work in these jobs levels of worker exposure to crystalline silica showed high variability, so that it was impossible to establish if in the medium-long term, they were lower than the Threshold Limit Values with a set probabilistic certainty (OTL test, confidence level 95%). In the remaining jobs the assessment of occupational exposures to crystalline silica showed a low probability of exceeding the Threshold Limit Values.

Ever changing problems in agricultural weed control require periodic introduction of new herbicides. Imidazo[4,5-c]pyrazoles, which were considered of interest as potential herbicides, were synthesized and examined for the pre-emergence, post-emergence, and post-transplant control of weeds in rice against broadleaf and grass weed species. The data obtained suggest that some imidazo[4,5-c]pyrazoles have potential herbicidal activity against a wide range of weeds, with 5-methyl, 5-thiomethyl, and 5-unsubstituted derivatives being the most effective. No herbicidal activity was observed in the 5-methylsulfonylimidazo[4,5-c]pyrazole and imidazo[4,5-c]pyrazolone series.

Ethyl 2-amino-3-methoxycarbonyl-4-oxo-2-pentenoate (3) reacts with hydroxylamine or hydrazines to give isoxazole and pyrazole ortho-dicarboxylic acid esters 4 and 5, respectively. Partial hydrolysis of diesters 4 and 5 afforded the corresponding dicarboxylic acid monoesters 6 and 7. Amidation of the intermediate acid chlorides 8,9 followed by hydrolysis of 4-methylesters 10, 11 gave the title compounds 1 and 2, respectively.

A Local Health Unit in the Umbria Region of Italy carried out environmental investigations to estimate exposure to respirable particles among workers in a number of companies belonging to the ceramics and brick industries manufacturing categories.The purpose of this paper was to estimate the degree of agreement of two sampling methods, Dorr-Oliver and GS3 selectors. Both selectors are deemed to comply with the respirable particles sampling reported in European Standard EN 481/1993.For each worker, respirable particles and the quartz contained therein were collected using Dorr-Oliver and GS3 selectors simultaneously, so that quartz exposure was also measured.The comparison between the two series of airborne concentrations of respirable particles (collected with the two selectors), showed statistically significant differences (p0.05 with Student's t test). Moreover, Pearson's coefficient showed a low correlation between the two series of data. A similar conclusion was obtained analysing quartz airborne concentrations. The results seem to confirm that the two sampling methods possess a different capture power ofparticles as a function of their size.

The gradual increase of substances coming onto the market, many of which are still not classified in terms of hazard for worker's health, in addition to those classified as carcinogens by the European Economic Community, imposes a review of the implementation of protective measures foreseen in specific regulations, also with the aim of assessing worker exposure.For this purpose, the SPSAL (Prevention and Safety at the Workplace Service) of ASL (Local Health Unit) No. 2, Umbria Region, in 1996, when Law No. 626/94 came into force, started a project aimed at identifying the companies located in the Unit's territory that used and/or produced carcinogens in their production cycle. In a sample of these companies, divided by category (wood,fuel distributors, engineering, galvanization,foundries, brickworks, ceramics processing, tobacco industries, and companies specializing in removal and recovery of asbestos-containing materials) environmental investigations were carried out to verify the levels of worker exposure to the carcinogens thus identified. In some cases, sampling was repeated even after the implementation ofspecific remedial measures in order to verify their effectiveness in terms of reducing risk.The production cycle, the use or production of carcinogenic substances was investigated in 811 companies, where the number of exposed workers was 3821. The environmental sampling carried out showed levels of exposure to various carcinogens that were below the limits specified by law or recommended by the major industrial hygiene associations. Checks carried out after the improvements confirmed their effectiveness and a significant reduction in risk. The exposed workers were identified for the purposes of entry in a special register that could, in the long term, facilitate the reconstruction of occupational exposure to carcinogens. This will also facilitate correct insurance and pension benefits and any legal action that might be taken.

Ethyl 2-amino-3-methoxycarbonyl-4-oxo-2-pentenoate (3) reacts with hydroxylamine or hydrazines to give isoxazole and pyrazole ortho-dicarboxylic acid esters 4 and 5, respectively. Partial hydrolysis of diesters 4 and 5 afforded the corresponding dicarboxylic acid monoesters 6 and 7. Amidation of the intermediate acid chlorides 8,9 followed by hydrolysis of 4-methylesters 10, 11 gave the title compounds 1 and 2, respectively.

Ever changing problems in agricultural weed control require periodic introduction of new herbicides. Imidazo[4,5-c]pyrazoles, which were considered of interest as potential herbicides, were synthesized and examined for the pre-emergence, post-emergence, and post-transplant control of weeds in rice against broadleaf and grass weed species. The data obtained suggest that some imidazo[4,5-c]pyrazoles have potential herbicidal activity against a wide range of weeds, with 5-methyl, 5-thiomethyl, and 5-unsubstituted derivatives being the most effective. No herbicidal activity was observed in the 5-methylsulfonylimidazo[4,5-c]pyrazole and imidazo[4,5-c]pyrazolone series.