Chemical sensitivity exposure

Health and Safety Factors. Butanediol is much less toxic than its unsaturated analogs. It is neither a primary skin irritant nor a sensitizer. Because of its low vapor pressure, there is ordinarily no inhalation problem. As with all chemicals, unnecessary exposure should be avoided. The LD q for white rats is 1.55 g/kg. 

What has become an even greater concern in recent years is the phenomenon known as multiple chemical sensitivity disorder triggered by exposures to many chemicals in the environment. Synthetic chemicals are all around us. They are in the products we use, in the clothes we wear, in the food we eat, in the air we breathe at work. Because chemicals are everywhere in the environment, it is not possible to escape exposure. For this reason many people have become sensitized to the chemicals around them. In fact, it is estimated that 15% of the population has become sensitized to common household and commercial products. For some people the sensitization is not too serious a problem. They may have what appears to be a minor allergy to one or more chemicals. Other people are much more seriously affected. They may feel tired all the time, and suffer from mental confusion, breathing problems, sore muscles, and a weakened immune system. Such people suffer from a condition known as Multiple Chemical Sensitivity (MCS). 

MCS may result from a single massive exposure to one or more toxic substances or repeated exposure to low doses. On one hand, some people may become chemically sensitive following a toxic chemical spill at work or in their community or after being sprayed directly with pesticides. On the other, individuals may develop this condition from spending forty hours each week in a poorly ventilated building where they breathe a profusion of chemicals common to our modem way of life. 

In nonindustrial settings, MCS substances are the cause of indoor air pollution and are the contaminants in air and water. Many of the chemicals which trigger MCS symptoms are known to be irritants or toxic to the nervous system. As an example, volatile organic compounds readily evaporate into the air at room temperature. Permitted airborne levels of such contaminants can still make ordinary people sick. When the human body is assaulted with levels of toxic chemicals that it cannot safely process, it is likely that at some point an individual will become ill. For some, the outcome could be cancer or reproductive damage. Others may become hypersensitive to these chemicals or develop other chronic disorders, while some people may not experience any noticeable health effects. Even where high levels of exposure occur, generally only a small percentage of people become chemically sensitive. 

Over the past decade, there have been considerable advances in our understanding of the immunobiological mechanisms that result in the quality of immune response necessary for the induction of chemical respiratory allergy. Experiments designed to characterize immune responses in mice to chemical sensitizers have demonstrated that different classes of chemical allergen stimulate the development of qualitatively discrete immune responses consistent with the selective emergence of functional subpopulations of T lymphocytes [16]. Thus, topical exposure of BALB/c strain mice to chemical contact allergens such as 2,4-dinitrochlorobenzene (DNCB) results in the induction of... 

Now, ten years later, I know that what was wrong with me was MCS. I ve probably had chemical sensitivities all my life. I do know this exposure in 1989 put me on my deathbed. But back then hardly anyone spoke of MCS. 

The only kind of therapy I could do was in a heated pool. They would put me in the water right in my wheelchair, and a therapist would help me to move a little bit. I did that three times a week, until we realized that I was chemically sensitive. Then I discontinued the water therapy to minimize my chemical exposures. Prior to that, I also started seeing alternative doctors who found I was depleted in all kinds of nutrients. They put me on amino acids and gave me IV vitamins but still hadn t made the environmental connection. 

One metabolic specialist I saw looked at my medical records and said, You re not going to find answers. We d spent thousands of dollars and I was still sick. She asked me what I d done that had helped, and I told her I ate organic foods and avoided chemical exposures. She told me to keep doing that, which was amazing to me. I don t usually mention my chemical sensitivities to mainstream doctors. 

When a person with MCS is subjected to ongoing chemical exposures by the people they live with or near—like in an apartment complex or in their own home—that person is being subjected to domestic assault, to the degree that the exposures are intentional or negligent. It s very demeaning and it undermines the confidence of the person with chemical sensitivities in a way that s very similar to what happens to victims of conventional domestic abuse. The insults and blows happen to people with chemical sensitivities and environmental illness on a daily basis, sometimes on an hourly basis. 

I ve been unhealthy all of my life but didn t realize I was chemically sensitive until I stopped smoking, in my thirties. Before that I felt so dead tired and sick all the time that I didn t know when I was reacting to chemical exposures. I couldn t understand what was wrong with me. After I quit, when I was around someone smoking a cigarette I felt like someone had stuck a hot poker up my nose. It was extremely painful. Now I have a chronic sinus condition and I am never without pain for one second, and I get sick from exposures to perfume, cleaning products and things like that, and many foods. 

Multiple chemical sensitivity has shaped Jill s life, but is not a significant part of her self-image. Although the symptoms she experiences from chemical exposures can be debilitating, she does not think of herself as handicapped or sick, nor does she seek out friendship or support from others with MCS. 

Scientists acknowledge that many substances contain chemicals known to be toxic in high concentrations. To chemically sensitive people, these and other substances can be harmful even in minute amounts. A whiff of hair spray, fresh paint or bug spray, for example, can be debilitating to a person with multiple chemical sensitivities. People with MCS must avoid chemical exposures or symptoms will persist or worsen and the illness will progress. 

Almost any symptom can occur in chemically sensitive people. The unifying factor in people with MCS is that their symptoms come and go in relation to chemical exposures that do not ordinarily affect others. The symptoms are diverse and unique to each person. The same chemical exposure may trigger different symptoms or none at all in different individuals. Usually more than one body system... 

While many of the symptoms reported by people with MCS are similar to known toxic reactions, they usually occur at exposure levels previously thought to be safe. Additionally, many chemically sensitive people experience symptoms vastly different from typical toxic reactions. 

Because people with MCS react to chemicals at levels that ordinarily do not affect others, chemical sensitivity is sometimes referred to as chemical allergy, although the mechanism is not the same as in the more traditional allergies. A person with MCS may react to animals, pollen, dust and mold with symptoms that are the same or different from those of traditional allergies. People with MCS may also have common allergy symptoms such as itchy eyes, nasal congestion, sinusitis, asthma, hives and other rashes that result from exposures to chemicals or typical allergens. 

By sending a self-addressed stamped envelope to this organization you will receive information for ordering a video tape, Multiple Chemical Sensitivity How Chemical Exposures May Be Affecting Your Health, featuring interviews with people who have MCS and... 

Liver disease may decrease hepatic metabolism resulting in enhanced responses to parent chemicals however, for many compounds, metabolism is only slightly impaired in moderate to severe liver disease. Disease-induced alterations in clearance and volume of distribution often act in opposite directions with respect to their effect on half-life. Bioavailability may be markedly increased in liver disease with portal/systemic anastomosis (the connection of normally separate parts so they intercommunicate) so that orally administered chemicals bypass hepatic first-pass metabolism. Altered receptor sensitivity has been observed for some chemical substances in liver cirrhosis. When liver tissue repair is inhibited by chemical co-exposure, even an inconsequential level of liver injury may lead to fulminating liver failure from a nonlethal exposure of hepatotoxic-ants. (Several articles, as reviewed by Dybing and Spderlund 1999.)... 

Multiple chemical sensitivity (MCS) is characterized by a variety of adverse effects upon multiple organs that result from exposure to levels of common foods, drugs, and chemicals that do not affect most people. Symptoms include headaches, fatigue, lack of concentration, memory loss, asthma, and other often subjective responses following exposure. MCS has remained controversial because standard medical evaluations, such as blood biochemical screens, have failed to identify consistent physical or laboratory test abnormalities that would account for the symptoms. 

Sensitizer The tenn refers to a chemical that causes a substantial proportion of exposed people or animals to develop an allergic reaction in nonnal tissue after repeated exposure to the chemical. Sensitization becoming allergic. 

Emulsions prepared with gelatin that had been treated to minimize sensitizing impurities have relatively low sensitivities for exposures made in air, particularly at low irradiances. They show pronounced low intensity reciprocity failure (LIRF). The pure silver bromide emulsions do not show high intensity reciprocity failure (HIRF) for direct development (65,66), but may do so for physical development (66). Faelens obtained HIRF in silver chloride emulsions for both physical development and the same developer he used for direct development of his silver bromide emulsion (67). Silver chloride emulsions, however, are more prone to unintentional chemical sensitization than silver bromide, and it is uncertain to what extent some chemical sen-... 

The crossover also depends on the chemical sensitization. Gilman (263) found that a dye with ER = -0.5A V could spectrally sensitize a (S+Au)-sensitized emulsion to some extent, although the crossover for the corresponding unsensitized emulsion was between -0.79 and -0.89 V. Iridium-doped emulsions can be sensitized for internal image formation by dyes with even less negative potentials. Emulsions without chemical sensitization also can be sensitized by dyes with ER as high as -0.25 V when the exposure is made under vacuum (235). 

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