Human Health Effects Research Program
Research Findings
Exposure Data
- Communities of concern in the basin continue to be exposed to persistent toxic substances (PTSs) including PCBs, dioxins, furans, chlorinated pesticides, i.e., DDT, and mercury (Hanrahan et al. 1999; Stewart et al. 1999, Schantz et al. 1999; Johnson et al, 1998; Anderson et al. 1998; Dellinger et al. 1996; Fitzgerald et al. 1996; Lonky et al. 1996; and Schantz et al. 1996).
- Levels of some contaminants in Great Lakes sport fish are above the advisory limits set by the state and federal government (Dellinger et al. 1995, 1996).
- Residents in the Great Lakes basin ate more fish than the 6.5g/day often estimated for the U.S. population (Courval et. al. 1996; Fitzgerald et al. 1996; Schantz et al. 1996; Anderson et al. 1998; Hanrahan et al. 1999).
- Sport fisheaters consume 2-3 times more fish than the general U.S. population (Courval et al. 1999, 1996; Fitzgerald et al. 1996, 1999; Schantz et al. 1996, 1999, Anderson et al. 1998, Hanrahan et al. 1999.
- Fish consumption appears to be the major pathway of exposure for some PTSs (Fitzgerald et al. 1996, 1999; Stewart et al. 1999).
- Body burden levels of some PTSs in vulnerable populations are higher than in the general U.S. population. Body burdens for some of these contaminants are 2 to 4 times higher than those of the general U.S. population (Anderson et al. 1998; Hanrahan et al., 1997; Schantz et al. 1999, 1996).
- A significant trend of increasing body burden is associated with increased fish consumption (Fitzgerald et al. 1996, 1999; Falk et al. 1999; Hanrahan et al. 1999)
- Men consume more fish than women; men and women eat Great Lakes sport fish during most of their reproductive years (Courval et al.1996; Fitzgerald et al. 1996; Lonky et al, 1996; Waller et al. 1996; Hanrahan et al. 1999).
- Maternal consumption of Lake Ontario Great Lakes fish increases the risk of prenatal exposure to the most heavily chlorinated PCBs (Stewart et al. 1999).
- Maternal consumption of Lake Ontario Great lakes fish increases the risk of prenatal exposure to the most heavily chlorinated PCBs (Stewart et al. 1999).
- Data collected from 1980 to 1995 from Great Lakes sport fisheaters showed a decline in serum polychlorinated biphenyl levels from a mean of 24 parts per billion (ppb) in 1980 to 12 ppb in 1995. This decline was associated with an 83% decrease in the number of fish meals consumed. (Tee PG et al. 2003).
Sociodemographics Data
- A recent survey estimated that 4.7 million people consumed Great Lakes sport fish in a given year; 43.9% of the respondents were women (Tilden et al. 1997).
- Knowledge of and adherence to health advisories for Great Lakes sport caught fish varies across different populations (Fitzgerald et al. 1996; Waller et al. 1996; Tilden et al. 1997)
- Fifty percent of respondents to the survey who had eaten Great Lakes sport fish were aware of the health advisory for fish, and awareness differed significantly by race, sex, educational level, fish consumption, and state of residence (Tilden et al. 1997).
- Ninety-seven percent of American Indian men were aware of local advisories against consuming Great Lakes fish sport fish however, 80% of the men ate fish (Fitzgerald et al. 1999).
- Eighty percent of minorities who had eaten Great Lakes sport fish were unaware of the fish advisory, and awareness was especially low among women (Tilden et al. 1997).
- Fish is an essential component of diets of minority populations and Native Americans; they consume fish that tend to have higher levels of contaminants (Fitzgerald et al. 1996; Waller et al. 1996).
Health Effects Data
- Conception rate and the incidence of a live birth are lower in some women who are sport fish consumers (Courval et al. 1996).
- An association was found between men who consumed large amounts of sport fish and the risk of delayed conception in their spouses (Courval et al. 1999).
- Significant menstrual cycle reductions were indicated in women who reported consuming more than 1 meal per month of contaminated Great Lakes sport fish (Mendola et al. 1997).
- Two-thousand seven hundred and sixteen infants born between 1986 and 1991 to participants of the New York State Angler Cohort Study were studied with respect to duration of maternal consumption of contaminated fish and potential effects on gestational age and birth size. The data indicated no significant difference in gestational age or birth size in these infants from their mothers' lifetime consumption of fish. The researchers noted that biological determinants such as parity, and placental infarction and maternal smoking were significant determinants of birth size (Buck et al. 2003).
- Neurobehavioral and developmental deficits have been observed in newborns (12 to 24 hours after birth and again 25 to 48 hours after birth) of mothers who consumed approximately 2.3 meals per month of contaminated Lake Ontario fish (Lonky et al. 1996).
- The relationship between prenatal exposure to PCBs and performance on the Neonatal Behavioral Assessment Scale (NBAS) was assessed. The results indicated significant relationships between the most highly chlorinated PCBs and performance impairment on the habituation and autonomic tests of the NBAS at 25 - 48 hours after birth. No significant relationship was found between PCBs of lesser chlorination, DDE hexachlorobenzene, mirex, lead, or mercury on any NBAS performance test. (Stewart et al. 2000).
- The relationship between prenatal exposure to PCBs and performance on the Fagan Test of Infant Intelligence (FTII) was also assessed in the Oswego's infants at 6 months and again at 12 months. The results indicated a significant relationship between exposure to PCBs and poor performance on the FTII. No significant relationship was found between exposure to DDE or methylmercury on any tests of the FTII (Darvill et al. 2000).
- The relationship between prenatal exposure to PCBs and methylmercury (MeHg) and performance on the McCarthy Scales of Children's Abilities was assessed in 212 children. Negative associations between prenatal MeHg exposure and McCarthy performance were found in subjects with higher levels of prenatal PCB exposure at 38 months. However, no relationship between PCBs and MeHg and McCarthy performance was observed when the children were reassessed at 54 months. These results partially replicated the findings of others and suggest that functional recovery may occur. The researchers concluded that the interaction between PCBs and MeHg can not be considered conclusive until it has been replicated in subsequent investigations (Stewart et al. 2003a).
- Response inhibition in preschool children exposed prenatally to PCBs may be due to incomplete development of their nervous system. One hundred and eighty-nine children in the Oswego study were tested using a continuous performance test. The researchers measured the splenium of the corpus callosum, a pathway implicated in the regulation of response inhibition, in these children by magnetic resonance imaging. The results indicated the smaller the splenium, the larger the association between PCBs and the increased number of errors the children made on the continuous performance test. The researchers suggest if the association between PCBs and response inhibition is indeed causal, then children with suboptimal development of the splenium may be particularly vulnerable to these effects (Stewart et al. 2003b).
- The exposed children are now three years of age and initial test results for memory, verbal, and perceptual performance indicate their score is lower than children from mothers who consumed low amounts or no fish (Stewart et al.1998).
- Self-reported liver disease, diabetes, and muscle/joint pain may be associated with exposure to PCBs and other contaminants via fish consumption (Dellinger et al. 1997).
- PCBs and dichlorodiphenyl dichloroethene (DDE) were markedly elevated in an adult fisheating cohort. Exposure to PCBs, not DDE, was associated with lower scores on several measures of memory and learning (Schantz et al. 2000).
- Serum PCB levels and consumption of Great Lakes fish were significantly associated with lower levels of thyroxine (T4 ) in women and men. In contrast, fish consumption, but not PCB serum levels, was significantly and inversely associated with triiodothyronine (T3 ) in men (Persky et al. 2001).
- Parents exposed to PCBs and DDE had a higher than expected proportion of male children than female children if the father had elevated PCB levels (Karmaus et al. 2002).
- Conception rate and the incidence of a live birth ….. add reference - Courval et al, 1996; Buck et al. 2000
