Pesticide inhalation

Your entire respiratory system can be burned by some pesticides, making it difficult to breathe. Other pesticides inhaled may not harm your respiratory system, but are carried quickly in your blood throughout your whole body where they can canse harm in varions ways. 

EXPOSURE ROUTES occupational exposure formulation, manufacture, and field application of this pesticide inhalation skin adsorption ingestion eye and skin contact contaminated air, water, soil, fish, and other aquatic organisms... 

Estimates are that 5,000 employees of lawn care companies created SZ of Che 80 million lawns in Che USA in 1980. Pesticides most used include preemergent grass weed, broadleaf weed and insect control pesticides. Applicators applying these pesticides are exposed for periods of six to eight weeks. Heasurements made Co determine exposure showed long term exposure resulted in very low levels of pesticide inhalation. Also, pesticide concentrations reaching the... 

The different effects produced by various routes of entry must also be considered. Oral-inhalative coefficients were calculated from the ratio of oral LD50 to inhalative LD50, to obtain a scale of substance air concentration to oral entry doses that allowed for exposure time and volume of inhaled air. For the majority of pesticides, inhalation exposures produce higher levels than oral entry (Voi-tenko et al. 1984). This finding is important in view of the fact that acceptable daily intakes were established on the basis of oral administration of pesticides. 

In a case-control study of pesticide factory workers in Brazil exposed to methyl parathion and formulating solvents, the incidence of chromosomal aberrations in lymphocytes was investigated (De Cassia Stocco et al. 1982). Though dichlorodiphenyltrichloroethane (DDT) was coformulated with methyl parathion, blood DDT levels in the methyl parathion-examined workers and "nonexposed" workers were not significantly different. These workers were presumably exposed to methyl parathion via both inhalation and dermal routes however, a dose level was not reported. The exposed workers showed blood cholinesterase depressions between 50 and 75%. However, the baseline blood cholinesterase levels in nonexposed workers were not reported. No increases in the percentage of lymphocytes with chromosome breaks were found in 15 of these workers who were exposed to methyl parathion from 1 week to up to 7 years as compared with controls. The controls consisted of 13 men who had not been occupationally exposed to any chemical and were of comparable age and socioeconomic level. This study is limited because of concomitant exposure to formulating solvents, the recent history of exposure for the workers was not reported, the selection of the control group was not described adequately, and the sample size was limited. 

Figure 3-5 graphically depicts the information that currently exists on the health effects of methyl parathion in humans and animals by various routes of exposure. The available literature reviewed concerning the health effects of methyl parathion in humans described case reports of longer-term studies of pesticide workers and case reports of accidental or intentional ingestion of methyl parathion. The occupational exposure is believed to be via the dermal and inhalation routes. The information on human exposure is limited in that the possibility of concurrent exposure to other pesticides or other toxic substances cannot be quantified. 

EPA 1978e. Teratology and acute toxicity of selected chemical pesticides administered by inhalation. Research Triangle Park, NC U.S. Environmental Protection Agency, Office of Research and Development, Health Effects Research Laboratory. EPA-600/1-78-003 NTIS PB-277 077. 

The most important routes of exposure to endosulfan for the general population are ingestion of food and the use of tobacco products with endosulfan residues remaining after treatment. Farmers, pesticide applicators, and individuals living in the vicinity of hazardous waste disposal sites contaminated with endosulfan may receive additional exposure through dermal contact and inhalation. 

In occupational settings, exposure to endosulfan is mainly via the dermal and inhalation routes. Although workers involved in the manufacture and formulation of pesticide products containing endosulfan are potentially exposed to high concentrations of the compound, actual exposure is probably limited by the use of engineering controls and personal protection equipment. The highest documented dermal and inhalation exposures have been reported for agricultural workers involved in the spray... 

For most chemicals, inhalation is the main route of entry into the body. However, certain chemicals (e.g. phenol, aniline, certain pesticides) can penetrate intact skin and so become absorbed into the body. This may occur through local contamination, e.g. from a liquid splash, or through exposure to high vapour concentrations. Special precautions to avoid skin contact are required with these chemicals and potential exposure via skin absorption has to be taken into account when assessing the adequacy of control measures. Chemicals able to penetrate intact skin are listed in Table 4.2. 

Applicators, mixers, loaders, and others who mix, spray, or apply pesticides to crops face potential dermal and/or inhalation exposure when handling bulk quantities of the formulated active ingredients. Although the exposure periods are short and occur only a few times annually, an estimate of this exposure can be obtained by quantifying the excreted polar urinary metabolites. Atrazine is the most studied triazine for potential human exposure purposes, and, therefore, most of the reported methods address the determination of atrazine or atrazine and its metabolites in urine. To a lesser extent, methods are also reported for the analysis of atrazine in blood plasma and serum. 

Exposure of organisms to pesticides occurs through contact or inhalation. Inhalation exposure can be assessed using some of the active samplers discussed in the previous section, for example air samplers mimicking respiratory systems. Contact exposure can be assessed using samplers that represent collection by horizontal or vertical surfaces, or combinations of these orientations. This article addresses only the first part of this process, i.e., consideration of techniques for sampling sprays in the environment. 

FCS0 is a lethal (fatal) concentration causing death in 50% of laboratory animals when the pesticide is absorbed through the respiratory tract (inhalation) as a steam or aerosol. 

Pesticide poisoning incidents from 1959-68 in Uzbekistan were analyzed. The acute poisoning analysis permitted us to divide sufferers into three groups the first indudes workers who have direct contact with pestiddes the second includes collective farm workers who worked in the fields shortly after the crops were treated and the third includes people who suffered the effects of pestiddes introduced into their bodies through water, food, and inhalation. 

Duration and route of exposure can influence the interpretation of biological markers for instance, in some cases, pesticides that are inhaled remain in systemic circulation longer than those that are ingested. Compounds characterized by a slow process of dermal absorption can give rise to prolonged kinetics if compared to the kinetics following ingestion or inhalation of the same compounds. 

Means and standard deviations for these distributions were normalized to daily breathing rates (m3/day), and an acceptable range was defined. It was assumed that the "day" represents the duration of time within a working day that chlorpyrifos may be handled by an individual (0.25 to 6.0 hr). It was also assumed that exposures would be negligible for the remainder of the working day following application or other contact. Both the dermal and inhalation exposures were assumed to follow lognormal distributions, which is consistent with common practice for exposure data distributions (for example, in the Pesticide Handlers Exposure Database, PHED). 

Due to the low volatility of cyromazine and the use of water-soluble bags for packaging the Trigard formulation, the main routes of exposure were expected to be from direct contact with the product or spray mixture on contaminated surfaces. Previous experience with pesticides worker exposure studies indicated that exposure from vapors or spray mist would be a minor factor. This can easily be confirmed by the PHED or similar published sources however, the extent of exposure from inhaling the product as dust is less well known. This route of exposure was also assumed to be minor, particularly with the use of water-soluble bag packaging. Given the low mammalian toxicity of cyromazine, the operators did not wear respiratory protection. 

Colorless to white hygroscopic crystals that are odorless. Pesticide grade is often dyed blue. This material is hazardous through inhalation, skin absorption, penetration through broken skin, and ingestion, and produces local skin/eye impacts. 

Pharmacologically, carbofuran inhibits cholinesterase, resulting in stimulation of the central, parasympathetic, and somatic motor systems. Sensitive biochemical tests have been developed to measure cholinesterase inhibition in avian and mammalian brain and plasma samples and are useful in the forensic assessment of carbamate exposure in human and wildlife pesticide incidents (Bal-lantyne and Marrs Hunt and Hooper 1993). Acute toxic clinical effects resulting from carbofuran exposure in animals and humans appear to be completely reversible and have been successfully treated with atropine sulfate. However, treatment should occur as soon as possible after exposure because acute carbofuran toxicosis can be fatal younger age groups of various species are more susceptible than adults (Finlayson et al. 1979). Carbofuran labels indicate that application is forbidden to streams, lakes, or ponds. In addition, manufacturers have stated that carbofuran is poisonous if swallowed, inhaled, or absorbed through the skin. Users are cautioned not to breathe carbofuran dust, fumes, or spray mist and treated areas should be avoided for at least 2 days (Anonymous 1971). Three points are emphasized at this juncture. First, some carbofuran degradation... 

The Food Quality Protection Act (FQPA) of 1996 mandated that the US EPA carry out risk assessments that consider the cumulative effects of exposure to pesticides having a common mechanism of toxicity, as well as consider exposure to each pesticide by various routes of exposure (e.g., dermal, dietary, inhalation) and sources (e.g., residues in food and water) in an aggregate manner [19]. To accomplish this, there needs to be sufficient evidence supporting a common adverse effect that is associated with a common mechanism of action in specific target tissues. To date, the required criteria necessary to establish a common mechanism of toxicity with a specific toxic effect for the pyrethroids are not available [1,8,98]. 

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