Blood contamination in children's saliva: prevalence, stability, and impact on the measurement of salivary cortisol, testosterone, and dehydroepiandrosterone.

The prevalence, stability, and impact of blood contamination in children's saliva on the measurement of three of the most commonly assayed hormones were examined. Participants were 363 children (47% boys; ages 6-13 years) from economically disadvantaged families who donated saliva samples on 2 days in the morning, midday, and late afternoon. Samples (n=2178) were later assayed for cortisol (C), testosterone (T), and dehydroepiandrosterone (DHEA). To index the presence of blood (and its components) in saliva, samples were assayed for transferrin. Transferrin levels averaged 0.37 mg/dl (SD=0.46, range 0.0-5.5, Mode=0), and were: (1) highly associated within individuals across hours and days, (2) positively correlated with age, (3) higher for boys than girls, (4) higher in PM than AM samples, and (5) the highest (>1.0 mg/dl) levels were rarely observed in samples donated from the same individuals. Transferrin levels were associated with salivary DHEA and C, but less so for T. As expected, the relationships were positive, and explained only a small portion of the variance. Less than 1% of the statistical outliers (+2.5 SDs) in salivary hormone distributions had correspondingly high transferrin levels. We conclude that blood contamination in children's saliva samples is rare, and its effects on the measurement of salivary hormones is small. Guidelines and recommendations are provided to steer investigators clear of this potential problem in special circumstances and populations.

Predictors of resilience in maltreated and nonmaltreated Latino children.

To date, few studies have sought to investigate the effects of child maltreatment and processes influencing maladaptation and resilience in Latino children. In the current investigation, multiple aspects of functioning, personal resources, and relationship features were examined in school-age maltreated and nonmaltreated Latino children. Maltreated Latino children were found to have fewer areas of resilient functioning. Ego-resiliency and ego-control, as personal resources, and the ability to form a positive relationship with an adult figure outside of the immediate family predicted resilience. However, certain aspects of interpersonal functioning were differentially related to resilience for maltreated and nonmaltreated Latino children. These findings have implications for understanding how resilience can be promoted in maltreated and nonmaltreated Latino children.

Persistent organic pollutants in plastic marine debris found on beaches in San Diego, California.

Plastic debris were collected from eight beaches around San Diego County, California. Debris collected include: pre-production pellets and post-consumer plastics including fragments, polystyrene (PS) foam, and rubber. A total of n = 2453 pieces were collected ranging from <5 mm to 50 mm in size. The plastic pieces were separated by type, location, and appearance and analyzed for polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs), dichlorodiphenyltrichloroethane (DDT) and its breakdown products, and chlordanes. PAH concentrations ranged from 30 ng g(-1) to 1900 ng g(-1), PCBs from non-detect to 47 ng g(-1), chlordanes from 1.8 ng g(-1) to 60 ng g(-1), and DDTs from non-detect to 76 ng g(-1). Consistently higher PAH concentrations found in PS foam samples (300-1900 ng g(-1)) led us to examine unexposed PS foam packaging materials and PS virgin pellets. Unexposed PS foam contained higher concentrations of PAHs (240-1700 ng g(-1)) than PS virgin pellets (12-15 ng g(-1)), suggesting that PAHs may be produced during manufacturing. Temporal trends of debris were investigated at one site, Ocean Beach, where storm events and beach maintenance were found to be important variables influencing debris present at a given time.