Acrolein respiratory toxicity

Acrolein was the most toxic of 15 herbicides tested for toxicity to fish (USEPA 1980). Responses by rainbow trout (Oncorhynchus mykiss) surviving 77 pg acrolein/L, a concentration that killed 50% in about 21 h, were characteristic of respiratory irritants (McKim et al. 1987). These responses included a steady increase in cough rate decreases in ventilation rate, oxygen utilization, and heart... 

The largest number of studies of the toxicity of acrolein in animals was conducted by way of inhalation, probably because acrolein has an appreciable vapor pressure under ambient conditions and inhalation is the principal exposure for humans (Beauchamp et al. 1985). Because of their intolerance to sharp and offensive odor and to intense irritation of conjunctiva and upper respiratory tract, humans have not suffered serious intoxication from acrolein. The strong lacrimatory effect of acrolein is usually a warning to occupational workers. Physiological perception of acrolein by humans begins at about 500 to 1000 pg/L air with eye and nasal irritation. The irritating effects compel afflicted individuals to immediately leave the polluted area (Beauchamp etal. 1985). Laboratory animals died from inhalation of 8000 to 11,000 pg/L after 4 to 6 h, mice from 875,000 pg/L after 1 min, and rats from 660 pg/L for 24 days (Table 10.4). Animals dying from... 

McKim, J.M., P.K. Schmeider, G.J. Niemi, R.W. Carlson, and T.R. Henry. 1987. Use of respiratory-cardiovascular responses of rainbow trout (Salmo gairdneri) in identifying acute toxicity syndromes in fish. Part 2. Malathion, carbaryl, acrolein and benzaldehyde. Environ. Toxicol. Chem. 6 313-328. 

In a study conducted with volunteers, a 20% decrease in respiratory rate was seen after an acute exposure to a low-level concentration of acrolein throat irritation occurred after 10 minutes (Weber-Tschopp et al. 1977). In the same study, the concentration of acrolein in the air was gradually increased from 0 to 0.6 ppm during 35 minutes and was kept at that level for an additional 5 minutes. In this case, there was a 25% decrease in respiratory rate at 0.6 ppm, and throat irritation was noticed at 0.43 ppm. The significance of the decrease in respiratory rate is not clear, but in animals, particularly rodents, it is considered to represent a reflex response to protect the respiratory tract from toxicants (Alarie 1973). In the case reported by Gosselin et al. (1979), death was presumably caused by inhalation of acrolein from an overheated fryer. Cellular desquamation of the bronchial lining and miscellaneous debris in the bronchial lumen were observed. 

The respiratory system is the primary target of acrolein toxicity, although dermal and ocular effects also occur. Acute exposure to acrolein results in irritation to the upper respiratory tract, skin, and eyes. Few other organ systems have been shown to exhibit significant effects from exposure. 

Organic compounds containing a carbonyl functional group, J C=0, such as aldehydes, ketones, esters, and carboxylic acids, exhibit a low order of toxicity. The lower aldehydes, such as formaldehyde, acetaldehyde, and acrolein, are severe irritants to the eyes and respiratory tract. Acrolein is a severe lachry-mator. Lower carboxylic acids are corrosive substances. Formic acid is a poison, but the toxic effects arise as a result of lowering of the blood pH below normal levels and have little to do with the carbonyl group in the molecule. 

Acrolein is a highly toxic componnd that can severely damage the eyes and respiratory system and bnm the skin. Ingestion can canse acnte gastrointestinal pain with pnhnonary congestion. 

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