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Although the toxic effects of lead have been known for centuries, lead intoxication is still widespread in the United States. Without baseline tests of neuropsychological, neurobehavioral and neurophysiological testing it may be difficult to detect subtle changes in neurological function after lead exposure. This may be further confounded by partial chelation treatment and exposure to neurotoxic mixtures or inability to quantitate alcohol consumption. We undertook a cross-sectional study to address these problems in 24 exposed and 29 control subjects in a plant that manufactured electrical components using fritted leaded glass to coat capacitors and transistors. Potentially exposed workers had blood lead levels ranging between 3 micrograms/dL to 135 micrograms/dL. Industrial hygiene monitoring revealed the plant's air lead levels ranged from 61 micrograms/m3 to 1,700 micrograms/m3 in excess of OSHA permissible exposure limits of 40 micrograms/m3/10 hr day. Using a specially designed battery of neurophysiological, neurobehavioral and neuropsychological screening tests, we demonstrated a significant difference from controls in measures of psychomotor speed, motor strength and verbal memory. Although limited by the cross-sectional design, these findings support the hypothesis that the battery of neurophysiological, neuropsychological and neurobehavioral tests can detect a significant inter-group differences between lead-exposed and control subjects.

Ethylene oxide is now frequently used to chemically sterilize heat-sensitive materials in the hospital setting. Previous reports of neurotoxic effects of ethylene oxide have been described in animals and humans. Recent reports suggest that cognitive deficits may be associated with chronic low-level ethylene oxide exposure. We undertook this study of hospital workers with chronic ethylene oxide exposure and compared them with a non-exposed control group in an attempt to detect neurological and neuropsychological abnormalities. Ethylene oxide breathing zone levels of up to 250 ppm in exposed subjects were reported. All evaluations were done without examiners' knowledge of exposure status of the subjects. The exposed group was found to have a statistically significant lower P300 amplitude, bilaterally hypoactive distal deep tendon reflexes and poorer performance on neuropsychological tests involving psychomotor speed. Exposed subjects acknowledged more symptoms and higher levels of depression and anxiety. Nerve conduction velocities and EEG spectral analysis were similar in both exposed and control groups as were scores on most psychological tests. Based upon this information and prior reports, ethylene oxide should be considered in a differential diagnosis of neuropsychological, peripheral and central nervous system dysfunction in workplace settings associated with ethylene oxide exposure.

This study examines how teachers teach when transfer students enter their classrooms during the school year. Eight schools participated, two from each of four community types: agricultural, military, urban, and stable. According to the teachers, transfer students experience learning problems because schools use different curricula and new students miss instruction while adjusting. However, these beliefs about the impact of transfer did not predict strategies teachers used to identify and address educational needs of transfer students. Most teachers outside agricultural communities planned their teaching as if their entire class remained with them from September to June even though as many as 50% of their students would transfer schools. The inconsistency of teacher beliefs and strategies may be due to teacher goals for integrating new students into classwork, to the limits teachers set to their responsibility for transfer students’ education, and to an assumption of population stability that underlies the educational system.

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Ethylene Oxide is widely used to sterilize heat-sensitive materials. Acute and chronic neurogenic effects to the central and peripheral nervous system in man and animals have been described. To assess the chronic, subtle neuropsychologic effects of ethylene oxide, we performed a cross-sectional study of 25 hospital central supply workers exposed to low levels of ethylene oxide and 24 unexposed control workers. Subjects were tested using a neuropsychological screening battery by examiners blinded to exposure status. Testing results were reviewed independently by two neuropsychologists without knowledge of exposure. Subject status was categorized as normal, "impaired," or disagreement (between the two neuropsychologists). There were significantly more subjects concordantly judged as impaired in the exposed group versus the control group (chi 2 (2) = 6.0861, p less than 0.05). Although limited by the cross-sectional study design and the global categorization, these findings suggest that CNS dysfunction and cognitive impairment may result from chronic ethylene oxide exposure in hospital central supply units.

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