Skin absorption chemicals

Acrolein is highly toxic by skin absorption. Brief contact may result in the absorption of harmful and possibly fatal amounts of material. Skin contact causes severe local irritation and chemical bums. Poly(vinyl chloride) coated protective gloves should be used (99). 

Strong acids and strong alkaUes can severely bum the skin, chromium compounds can produce skin rashes, and repeated exposure to solvents causes removal of natural oils from the skin. Infection is always a concern for damaged skin. Absorption through the skin is possible for materials that are appreciably soluble iu both water and oil, eg, nitrobenzene, aniline, and tetraethyllead. Other materials can be absorbed if first dissolved iu extremely good solvents, eg, dimethyl sulfoxide. Subcutaneous iujection can occur accidentally by direct exposure of the circulatory system to a chemical by means of a cut or scratch or iuadvertent penetration of the skin with a hypodermic needle. 

Toxic chemicals can enter the body in various ways, in particular by swallowing, inhalation and skin absorption. Skin absorption may lead to dermatitis and this can be a most annoying complaint. Whereas some chemicals may have an almost universal effect on human beings, others may attack only a few persons. A person who has worked with a given chemical for some years may suddenly become sensitised to it and from then on be unable to withstand the slightest trace of that material in the atmosphere. He may as a result also be sensitised not only to the specific chemical that caused the initial trouble but to a host of related products. Unfortunately a number of chemicals used in the plastics industry have a tendency to be dermatitic, including certain halogenated aromatic materials, formaldehyde and aliphatic amines. 

A good standard of personal hygiene is required to minimize exposure by ingestion or skin absorption of chemicals. The measures include ... 

Impervious clothing is essential when handling coiTosive chemicals, liquids liable to cause dermatitis, or chemicals toxic by skin absorption. 

Chemical PPE In a fire or thermal energy hazard, PPE worn by responders should meet, at a minimum, the criteria in 29 CER 1910.156 (e), Eire Brigade Standard, requiring turnout gear. In conditions where skin absorption of a hazardous substance may result in substantial possibility of immediate death, serious illness, or injury or impaired ability to escape, totally encapsulated chemical protective suits should be used. It is vital to keep heat resistance of the totally encapsulated suits and the heat resistance of any PPE used underneath or in conjunction with the totally encapsulated suits in mind any time there is a thermal hazard. 

Are totally encapsulating chemical protective suits (Level A) used in conditions where skin absorption of a hazardous substance may result in a substantial possibility of immediate death, immediate serious illness or injury, or impair the ability to escape ... 

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. 

All of these chemicals pose an inhalation hazard but a toxic dose could also be obtained through skin absorption or ingestion. Factors that were considered when selecting potential candidate chemicals include global production, physical state of the material (i.e., gas, liquid, or solid), chemicals likely to cause major morbidity or mortality, potential to cause public panic and social disruption, chemicals that require special action for public health preparedness, history of previous use by the military, and/or involvement in a significant industrial accident. 

SKIN This designation sometimes appears alongside a TLV or PEL. It refers to the possibility of absorption of the particular chemical through the skin and eyes. Thus, protection of large surface areas of skin should be considered to prevent skin absorption so that the TLV is not invalidated. 

The routes by which one may be exposed to chemical agents vary and include inhalation, ingestion, skin absorption, and local skin and eye impacts. Personnel exposed to any of these agents should be decontaminated immediately following the procedures outlined in Section 7.3 and given immediate medical attention. Refer to Chapter 3 for details about individual chemical agents including ... 

In industry, the quickest absorption occurs when a chemical is inhaled as a gas, a mist, or a dust. The next quickest is by mouth, and the slowest is through the skin, and, of course, only for those fat soluble chemicals that can be absorbed through the skin. Most chemicals are soluble only in water, if at all, and cannot be absorbed through the skin. As we have already seen, the skin acts as a barrier to absorption for chemicals that are not soluble in fat or oil. For skin absorption, the larger the area of skin involved and the longer the chemical is in contact, the greater is the response. 

Preventing exposure to hazardous industrial chemicals is a primary concern at industrial sites. Most sites contain a variety of chemical substances in gaseous, liquid, or solid form. These substances can enter the unprotected body by inhalation, skin absorption, ingestion, or through a puncture wound (injection). A contaminant can cause damage at the point of contact or can act systemically, causing a toxic effect at a part of the body distant from the point of initial contact. 

OECD has adopted an in vitro test for skin absorption potential (OECD TG 428, Skin Absorption In Vitro Method). According to this guideline, excised skin from human or animal sources can be used. The skin is positioned in a diffusion cell consisting of a donor chamber and a receptor chamber, between the two chambers. The test substance, which may be radio-labeled, is applied to the surface of the skin sample. The chemical remains on the skin for a specified time under specified conditions, before removal by an appropriate cleansing procedure. The fluid in the receptor chamber is sampled at time points throughout the experiment and analyzed for the test chemical and/or metabolites. 

In industrial experience, intoxication has occurred from inhalation of the dust or vapor or by skin absorption after direct contact. Fatal intoxication occurred in a chemical worker who spilled a solution of 2-aminopyridine on his clothing during a distillation he continued to work in contaminated clothing for 1.5 hours. Two hours later, he developed dizziness, headache, respiratory distress, and convulsions that progressed to respiratory failure and death it is probable that skin absorption was a major factor in this case. 

A 44-year-old male worker experienced a large skin area exposure to a mixture of CAC, benzene, and xylidine. The worker was put under a shower within 5 minutes of the accident, but shortly thereafter he began to have respiratory difficulties and experienced an apparent grand mal seizure. The patient was still comatose 2 years after the accident. Burns caused by the chloroacetyl chloride were believed to have enhanced skin absorption of the other two chemicals, although the relative contribution of the three chemicals to the... 

Hydrogen cyanide is extremely toxic hy ingestion, inhalation, skin absorption, and all routes of exposure. An oral dose of 50 mg could be lethal to humans (Patnaik, P. 1999. A Comprehensive Guide to the Hazardous Properties of Chemical Substances, 2nd ed.. New York John Wiley). Symptoms from acute poisoning include labored breathing, shortness of breath, paralysis, unconsciousness, and respiratory failure. Lower doses can cause headache, nausea and vomiting. Oral LDsoin mice is 3.7 mg/kg. Amyl nitrite is an effective antidote. 

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