Agency for Toxic Substances and Disease Registry 
Case Studies in Environmental Medicine (CSEM) 

Taking an Exposure History
Which Organ Systems Are Affected By Toxic Exposure?

Learning Objectives

Upon completion of this section, you will be able to

• explain what organ systems are often affected by toxic exposure.

Introduction

All organ systems (Table 2) can be targets of toxic exposures. Different toxins affect various and differing organ systems (Pope AM and Rall DP 1995).

Respiratory

The respiratory system is both a target organ and a portal of entry for toxicants. Asthma morbidity and death from asthma are increasing. More than 100 toxicants cause asthma, and many more can exacerbate it (Rom 1998).

Skin

Irritant and allergic contact dermatitis account for 90% of occupational skin disorders. Other skin disorders with occupational/environmental exposure etiologies include pigment alterations, chloracne, urticaria, and malignant neoplasms (Levy and Wegman 2000).

Liver and Kidney

Symptoms of liver disease due to toxic exposure can mimic viral hepatitis. About 4,000 new cases of renal disease of unknown etiology are diagnosed annually. Organic solvents and heavy metals are two classes of toxicants known to adversely affect renal function (Pope and Rall 1995).

Central Nervous System

Neurotoxicants can cause peripheral neuropathy, ataxia, parkinsonism, seizures, coma, and death. Many chemicals cause mild central nervous system depression that may be misdiagnosed as intoxication and, if undetected, can progress to psychoses or dementia. Sensory impairment can also be caused by exposure to toxicants (e.g., visual disturbances caused by methanol) and physical agents (e.g., hearing impairment caused by loud noise) (Pope and Rall 1995; Rom 1998).

Reproductive

Toxicants that target the female reproductive system can cause a wide variety of adverse effects. Changes in sexual behavior, onset of puberty, cyclicity, fertility, gestation time, pregnancy outcome, and lactation as well as premature menopause are among the potential manifestations of female reproductive toxicity. Exposure to lead, for example, can result in menstrual disorders and infertility.

Toxicants that target the male reproductive system can affect sperm count or shape, alter sexual behavior, and/or increase infertility. Carbon disulfide, for example, is known to disrupt male reproductive health.

Cardiovascular and Hematologic

The cardiovascular and hematologic systems are frequent targets of toxicants. Cardiovascular changes, as well as exacerbation of preexisting cardiovascular conditions, can result from exposure to noise and to chemicals such as carbon monoxide and tobacco smoke. Benzene can cause bone marrow changes leading to aplastic anemia, acute leukemia, and chronic myelogenous leukemia (Pope and Rall 1995; Rom 1998).

respiratory

asbestos, radon, cigarette smoke, glues

skin

dioxin, nickel, arsenic, mercury, cement (chromium), polychlorinated biphenyls (PCBs), glues, rubber cement

liver

carbon tetrachloride, methylene chloride, vinyl chloride

kidney

cadmium, lead, mercury, chlorinated hydrocarbon solvents

cardiovascular

carbon monoxide, noise, tobacco smoke, physical stress, carbon disulfide, nitrates, methylene chloride

reproductive

lead, carbon disulfide, methylmercury, ethylene dibromide

hematologic

arsenic, benzene, nitrates, radiation

neuropsychological

tetrachloroethylene, mercury, arsenic, toluene, lead, methanol, noise, vinyl chloride

Key Points

• All organ systems can be targets of toxic exposures.

Progress Check