Cancer and non-cancer health effects from food contaminant exposures for children and adults in California: a risk assessment.

BACKGROUND: In the absence of current cumulative dietary exposure assessments, this analysis was conducted to estimate exposure to multiple dietary contaminants for children, who are more vulnerable to toxic exposure than adults. METHODS: We estimated exposure to multiple food contaminants based on dietary data from preschool-age children (2-4 years, n=207), school-age children (5-7 years, n=157), parents of young children (n=446), and older adults (n=149). We compared exposure estimates for eleven toxic compounds (acrylamide, arsenic, lead, mercury, chlorpyrifos, permethrin, endosulfan, dieldrin, chlordane, DDE, and dioxin) based on self-reported food frequency data by age group. To determine if cancer and non-cancer benchmark levels were exceeded, chemical levels in food were derived from publicly available databases including the Total Diet Study. RESULTS: Cancer benchmark levels were exceeded by all children (100%) for arsenic, dieldrin, DDE, and dioxins. Non-cancer benchmarks were exceeded by >95% of preschool-age children for acrylamide and by 10% of preschool-age children for mercury. Preschool-age children had significantly higher estimated intakes of 6 of 11 compounds compared to school-age children (p<0.0001 to p=0.02). Based on self-reported dietary data, the greatest exposure to pesticides from foods included in this analysis were tomatoes, peaches, apples, peppers, grapes, lettuce, broccoli, strawberries, spinach, dairy, pears, green beans, and celery. CONCLUSIONS: Dietary strategies to reduce exposure to toxic compounds for which cancer and non-cancer benchmarks are exceeded by children vary by compound. These strategies include consuming organically produced dairy and selected fruits and vegetables to reduce pesticide intake, consuming less animal foods (meat, dairy, and fish) to reduce intake of persistent organic pollutants and metals, and consuming lower quantities of chips, cereal, crackers, and other processed carbohydrate foods to reduce acrylamide intake.

Evaluation of risk factors and a community intervention to increase control and treatment of asthma in a low-income semi-rural California community.

To better understand risk factors associated with current asthma in a low-income, ethnically diverse population, we analyzed pooled data from the 2004-2006 Behavioral Risk Factor Surveillance System survey conducted in Salinas, CA. We were particularly interested in modifiable risk factors, as the survey was conducted as part of a large community-based intervention that addresses asthma, obesity, and diabetes. We also conducted semi-structured interviews with key informants involved with the clinical, school, and community aspects of the intervention to inform the intervention's progress, and adapt practices and programs to reach those most in need. Of the 4925 adults in this analysis, 51% were Mexican-American and 32% lacked a high-school diploma; 227 women and 84 men had current asthma, and 194 were parents of children with current asthma; prevalences of 7.7%, 4.3%, and 7.0% respectively. Over 20% of women and men with asthma were current smokers and/or exposed to passive smoking, more than 50% reported less than the recommended 60 minutes or more of physical activity per day, and approximately 40% were obese or morbidly obese (42% of women and 36% of men compared to 26% of adults without asthma). Two of the strongest modifiable risk factors associated with current asthma and identified by the stepwise multiple regression models were: could not afford prescription medication(s) in the past 12 months (OR 2.5, p < 0.001 for adults with asthma, OR 1.8, p < 0.01 for parents of children with asthma) and morbid obesity (OR 3.4, p < 0.001 for adults with asthma). Among adults who reported one or more episodes of asthma in the past 30 days, 28% of women and 30% of men had not used a preventive medication, and 48% of women and 57% of men had not used a prescription asthma inhaler (20% had not used either). This study adds to the scarce body of literature on the prevalence of asthma and related risk factors in a predominately Mexican-American, semi-rural community, and illustrates how survey and key informant data can enhance knowledge of local study populations and guide interventions to improve asthma control and treatment.

The power of policy: a case study of healthy eating among children.

We used a case study approach to examine the nutritional effect of a policy to increase fruit and vegetable consumption in the Students Today Achieving Results for Tomorrow after-school program. The snack menu was changed in 44 after-school programs serving 8000 low-income and ethnically diverse elementary-school students. A comparison of previous and current snack menus identified a significant increase in fruit servings (83%) and no change in vegetable servings. We discuss the unintended consequences resulting from the menu changes.

Functional studies on native and mutated forms of perilipins. A role in protein kinase A-mediated lipolysis of triacylglycerols.

Perilipin A coats the lipid storage droplets in adipocytes and is polyphosphorylated by protein kinase A (PKA); the fact that PKA activates lipolysis in adipocytes suggests a role for perilipins in this process. To assess whether perilipins participate directly in PKA-mediated lipolysis, we have expressed constructs coding for native and mutated forms of the two major splice variants of the perilipin gene, perilipins A and B, in Chinese hamster ovary fibroblasts. Perilipins localize to lipid droplet surfaces and displace the adipose differentiation-related protein that normally coats the droplets in these cells. Perilipin A inhibits triacylglycerol hydrolysis by 87% when PKA is quiescent, but activation of PKA and phosphorylation of perilipin A engenders a 7-fold lipolytic activation. Mutation of PKA sites within the N-terminal region of perilipin abrogates the PKA-mediated lipolytic response. In contrast, perilipin B exerts only minimal protection against lipolysis and is unresponsive to PKA activation. Since Chinese hamster ovary cells contain no PKA-activated lipase, we conclude that the expression of perilipin A alone is sufficient to confer PKA-mediated lipolysis in these cells. Moreover, the data indicate that the unique C-terminal portion of perilipin A is responsible for its protection against lipolysis and that phosphorylation at the N-terminal PKA sites attenuates this protective effect.