Irritant formaldehyde

Inhaled gaseous compounds are absorbed in all parts of the respiratory system whereas particle size determines how deep into the airways the parti cles will he transported in the airstrearn. Shortness of breath is a typical sign of a chemical exposure that has affected the lungs, and it may be evoked through iminunological mechanisms (e.g., formaldehyde, ethyleneoxide), or through toxic irritation (formaldehyde, isocyanates, sulfur dioxide, nitrogen dioxide, Frequently the mechanism depends on the concentration ol the com... 

Formaldehyde, HCHO, is a primary and necessary constituent of the first five synthetic adhesives in the listing. It is a simple organic chemical first identified during the latter half of the 1800s. Its irritating and toxic odor and preservative properties were known from the time of its early development. It is a ubiquitous chemical, formed naturally in small quantities by every process of incomplete combustion as well as in normal biologic processes. The human body has a natural formaldehyde level of about 3 lg/g, ie, 3 parts per million (ppm) in the blood at all times. 

If acetal resins are processed at temperatures substantially above those recommended for the particular grade, minor amounts of formaldehyde may be Hberated. Formaldehyde (qv) is a colorless, lacrimatory gas with a pungent odor and is intensely irritating to mucous membranes. The human nose is sensitive to concentrations in the range of 0.1 to 0.5 ppm. The current threshold limit value for formaldehyde is 1 ppm. 

At high enough concentrations, PAN is a potent eye irritant and phytotoxin. On a smoggy day in the Los Angeles area, PAN concentrations are typically 5 to 10 ppb in the rest of the United States PAN concentrations are generally a fraction of a ppb. An important formation route for formaldehyde [50-00-0] HCHO, is reaction 9. However, o2onolysis of olefinic compounds and some other reactions of VOCs can produce HCHO and other aldehydes. 

Formaldehyde causes eye, upper respiratory tract, and skin irritation and is a skin sensitizer. Although sensory irritation, eg, eye irritation, has been reported at concentrations as low as 0.1 ppm in uncontrolled studies, significant eye/nose/throat irritation does not generally occur until concentrations of 1 ppm, based on controlled human chamber studies. Odor detection has commonly been reported to occur in the range of 0.06—0.5 ppm (133—135). 

Urea—formaldehyde use has been greatly restricted because of free formaldehyde (qv) emissions which can cause eye irritation and in some cases serious illness. Some attempts at developing formaldehyde-free urea-based materials are ongoing. 

LLDPE can present a certain health hazard when it bums, since smoke, fumes, and toxic decomposition products are sometimes formed in the process. Exposure to burning LLDPE can cause irritation of the skin, eyes, and mucous membranes of the nose and throat due to the presence of acrolein and formaldehyde (81). Toxicity of LLDPE pyrolysis products depends on temperature, heating rate, and the sample size (82—84). 

Phenol formaldehyde. Eormaldehyde is a respiratory irritant but is not classified as asthmagen. Powder coatings containing triglycidyl isocyanurate are possible asthmagens (unclassified)... 

Formaldehyde has been rated as a possible carcinogen by the United States Occupational Safety and Health Act (OSHA) rules and should be handled with due caution. It is also a strong lacrymator and choking respiratory irritant. It irritates the skin, eyes, and mucous membranes [76]. Since it is used for tanning leather, it is obvious that fonnaldehyde has a high potential for reactions with proteins. Formaldehyde gas is flammable and most formalin solutions contain significant amounts of methanol, which is also volatile, toxic, and flammable. 

The so-called El-emission class describes a wood panel presenting formaldehyde emission which is low enough to prevent any danger, irritation or inflammation of the eyes, nose and mouth mucous membranes. However, it is important that not only the boards themselves, but also the veneering and carpenter s adhesive resins, laquers, varnishes and other sources of formaldehyde are under control, since they also might contribute to the mixture steady state formaldehyde concentration [9]. Table 3 gives an overview on some European regulations. However, it is necessary here to introduce the principal types of composite wood products, especially panels, that are produced in this industry ... 

Observable Characteristics - Physical State (as shipped) Solid Color White Odor. Pungent and irritating like formaldehyde. 

Note The dipping reagent is to be preferred because of the strongly irritating effects of formaldehyde on the respiratory tract. Detection limits of ca. 10—40 ng have been reported for alkaloids [4] and 50 ng — 1 pg for -blockers [2, 3]. 

The pollutants most strongly damaging to human, animal, and sometimes plant health include ozone, fine particulate matter, lead, nitrogen oxides (NO ), sulfur oxides (SOJ, and carbon monoxide. Many other chemicals found in polluted air can cause lesser health impacts (such as eye irritation). VOC compounds comprise the bulk of such chemicals. Formaldehyde is one commonly mentioned pollutant of this sort, as is PAN (peroxyacyl nitrate). Such... 

Various aldehydes, alcohols, esters, and ketones are also found in exhaust gases, at concentrations up to several hundred parts per million. Formaldehyde and acrolein are outstanding eye irritants in the raw exhaust gases... 

Methanol is a dangerous fire hazard when exposed to heat or flame, and a moderate expl hazard when exposed to flame. It is a dangerous disaster hazard upon exposure to heat or flame, and can react vigorously with oxidizing materials. Methanol possesses distinct narcotic props, and is also a slight irritant to the mucous membranes. Its main toxic effect is exerted upon the nervous system, particularly the optic nerves and possibly the retinae. In the body the products formed by its oxidn are formaldehyde and formic acid, both of which are toxic. Because of the slowness with which it is eliminated, methanol should be regarded as a cumulative poison (Ref 5)... 

Various formaldehyde condensates have been developed to reduce the irritancy associated with formaldehyde while maintaining activity and these are described as formaldehyde-releasing agents or masked-formaldehyde compounds. 

Chemical disinfectants are limited in their use as air sterilants because of their irritant properties when sprayed. However, some success has been achieved with atomized propylene glycol at a concentration of 0.05-0.5 mgH and quaternary ammonium compounds (QACs) at 0.075% m be used. For areas which can be effectively sealed off for fumigation purposes, formaldehyde gas at a concentration of 1-2 mg H of air at a relative humidity of 80-90% is effective. 

EICEIO, a gas with an irritating smell. It is made industrially by the oxidation of methyl alcohol, and is used in the manufacture of phenol-formaldehyde and urea-formaldehyde resins and plastics. 

Babiuk, C., W.H. Steinhagen, and C.S. Barrow. 1985. Sensory irritation response to inhaled aldehydes after formaldehyde pretreatment. Toxicol. Appl. Pharmacol. 79 143-149. 

Formaldehyde (also a VOC) ETS building materials and fabrics cleaning fluids and adhesives. irritation to eye. nose and respiratory system allergy, carcinogenic. 

However, if you link the hydroxyl group with the methane molecule rather than the ethane, you get the potentially toxic chemical called methyl alcohol, or wood spirit. Similarly, if you add what s called an aldehyde group (-CHO) instead of the hydroxyl group, you will get one of a variety of chemicals called aldehydes, of which a common one is the gas formaldehyde (HCHO), widely used in the manufacture of plastics and glues. This gas can be an irritant and potentially dangerous if inhaled. 

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