An eleven-year study of chlorinated hydrocarbon insecticide residues in bovine fat in Illinois, 1972-1982

Bovine fat samples in Illinois were monitored for residues of chlorinated hydrocarbon insecticides from 1972 through 1982. The percentage of fat samples that were contaminated with all chlorinated hydrocarbons decreased during the 11-year study. The percentage of samples contaminated with DDT and its analogs decreased most markedly from 82.4% in 1972 to 2.1% in 1982. The percentage of samples contaminated with aldrin/dieldrin and heptachlor/heptachlor epoxide began to decline in 1980 and continued to decrease through 1982.     

HPLC-PFD determination of priority pollutant PAHs in water,sediment, and semipermeable membrane devices

High performance liquid chromatography coupled with programmable fluorescence detection was employed for the determination of 15 priority pollutant polycyclic aromatic hydrocarbons (PPPAHs) in water, sediment, and semipermeable membrane devices (SPMDs). Chromatographic separation using this analytical method facilitates selectivity, sensitivity (ppt levels), and can serve as a non-destructive technique for subsequent analysis by other chromatographic and spectroscopic techniques. Extraction and sample cleanup procedures were also developed for water, sediment, and SPMDs using various chromatographic and wet chemical methods. The focus of this publication is to examine the enrichment techniques and the analytical methodologies used in the isolation, characterization, and quantitation of 15 PPPAHs in different sample matrices.     

Mortality Risk in Pediatric Motor Vehicle Crash Occupants: Accounting for Developmental Stage and Challenging Abbreviated Injury Scale Metrics

Objective: Survival risk ratios (SRRs) and their probabilistic counterpart, mortality risk ratios (MRRs), have been shown to be at odds with Abbreviated Injury Scale (AIS) severity scores for particular injuries in adults. SRRs have been validated for pediatrics but have not been studied within the context of pediatric age stratifications. We hypothesized that children with similar motor vehicle crash (MVC) injuries may have different mortality risks (MR) based upon developmental stage and that these MRs may not correlate with AIS severity.

Methods: The NASS-CDS 2000–2011 was used to define the top 95% most common AIS 2+ injuries among MVC occupants in 4 age groups: 0–4, 5–9, 10–14, and 15–18 years. Next, the National Trauma Databank 2002–2011 was used to calculate the MR (proportion of those dying with an injury to those sustaining the injury) and the co-injury-adjusted MR (MR_MAIS) for each injury within 6 age groups: 0–4, 5–9, 10–14, 15–18, 0–18, and 19+ years. MR differences were evaluated between age groups aggregately, between age groups based upon anatomic injury patterns and between age groups on an individual injury level using nonparametric Wilcoxon tests and chi-square or Fisher's exact tests as appropriate. Correlation between AIS and MR within each age group was also evaluated.

Results: MR and MR_MAIS distributions of the most common AIS 2+ injuries were right skewed. Aggregate MR of these most common injuries varied between the age groups, with 5- to 9-year-old and 10- to 14-year-old children having the lowest MRs and 0- to 4-year-old and 15- to 18-year-old children and adults having the highest MRs (all P <.05). Head and thoracic injuries imparted the greatest mortality risk in all age groups with median MR_MAIS ranging from 0 to 6% and 0 to 4.5%, respectively. Injuries to particular body regions also varied with respect to MR based upon age. For example, thoracic injuries in adults had significantly higher MR_MAIS than such injuries among 5- to 9-year-olds and 10- to 14-year-olds (P =.04; P <.01). Furthermore, though AIS was positively correlated with MR within each age group, less correlation was seen for children than for adults. Large MR variations were seen within each AIS grade, with some lower AIS severity injuries demonstrating greater MRs than higher AIS severity injuries. As an example, MR_MAIS in 0- to 18-year-olds was 0.4% for an AIS 3 radius fracture versus 1.4% for an AIS 2 vault fracture.

Conclusions: Trauma severity metrics are important for outcome prediction models and can be used in pediatric triage algorithms and other injury research. Trauma severity may vary for similar injuries based upon developmental stage, and this difference should be reflected in severity metrics. The MR-based data-driven determination of injury severity in pediatric occupants of different age cohorts provides a supplement or an alternative to AIS severity classification for pediatric occupants in MVCs.     

An eleven‐year study of chlorinated hydrocarbon insecticide residues in bovine fat in illinois, 1972–1982

Abstract

Bovine fat samples in Illinois were monitored for residues of chlorinated hydrocarbon insecticides from 1972 through 1982. The percentage of fat samples that were contaminated with all chlorinated hydrocarbons decreased during the 11‐year study. The percentage of samples contaminated with DDT and its analogs decreased most markedly from 82.4% in 1972 to 2.1% in 1982. The percentage of samples contaminated with aldrin/dieldrin and heptachlor/heptachlor epoxide began to decline in 1980 and continued to decrease through 1982.     

Evaluation of developmental metrics for utilization in a pediatric advanced automatic crash notification algorithm

Objective: Appropriate treatment at designated trauma centers (TCs) improves outcomes among injured children after motor vehicle crashes (MVCs). Advanced Automatic Crash Notification (AACN) has shown promise in improving triage to appropriate TCs. Pediatric-specific AACN algorithms have not yet been created. To create such an algorithm, it will be necessary to include some metric of development (age, height, or weight) as a covariate in the injury risk algorithm. This study sought to determine which marker of development should serve as a covariate in such an algorithm and to quantify injury risk at different levels of this metric.

Methods: A retrospective review of occupants age < 19 years within the MVC data set NASS-CDS 2000–2011 was performed. R² values of logistic regression models using age, height, or weight to predict 18 key injury types were compared to determine which metric should be used as a covariate in a pediatric AACN algorithm. Clinical judgment, literature review, and chi-square analysis were used to create groupings of the chosen metric that would discriminate injury patterns. Adjusted odds of particular injury types at the different levels of this metric were calculated from logistic regression while controlling for gender, vehicle velocity change (delta V), belted status (optimal, suboptimal, or unrestrained), and crash mode (rollover, rear, frontal, near-side, or far-side).

Results: NASS-CDS analysis produced 11,541 occupants age < 19 years with nonmissing data. Age, height, and weight were correlated with one another and with injury patterns. Age demonstrated the best predictive power in injury patterns and was categorized into bins of 0–4 years, 5–9 years, 10–14 years, and 15–18 years. Age was a significant predictor of all 18 injury types evaluated even when controlling for all other confounders and when controlling for age- and gender-specific body mass index (BMI) classifications. Adjusted odds of key injury types with respect to these age categorizations revealed that younger children were at increased odds of sustaining Abbreviated Injury Scale (AIS) 2+ and 3+ head injuries and AIS 3+ spinal injuries, whereas older children were at increased odds of sustaining thoracic fractures, AIS 3+ abdominal injuries, and AIS 2+ upper and lower extremity injuries.

Conclusions: The injury patterns observed across developmental metrics in this study mirror those previously described among children with blunt trauma. This study identifies age as the metric best suited for use in a pediatric AACN algorithm and utilizes 12 years of data to provide quantifiable risks of particular injuries at different levels of this metric. This risk quantification will have important predictive purposes in a pediatric-specific AACN algorithm.     

A spatially explicit framework for quantifying downstream hydrologic conditions

Continued improvements in spatial datasets and hydrological modeling algorithms within Geographic Information Systems (GISs) have enhanced opportunities for watershed analysis. With more detailed hydrology layers and watershed delineation techniques, we can now better represent and model landscape to water quality relationships. Two challenges in modeling these relationships are selecting the appropriate spatial scale of watersheds for the receiving stream segment, and handling the network or pass-through issues of connected watersheds. This paper addresses these two important issues for enhancing cumulative watershed capabilities in GIS. Our modeling framework focuses on the delineation of stream-segment-level watershed boundaries for 1:24 000 scale hydrology, in combination with a topological network model. The result is a spatially explicit, vector-based, spatially cumulative watershed modeling framework for quantifying watershed conditions to aid in restoration. We demonstrate the new insights available from this modeling framework in a cumulative mining index for the management of aquatic resources in a West Virginia watershed.     

Stream ecosystem response to limestone treatment in acid impacted watersheds of the Allegheny Plateau.

Restoration programs are expanding worldwide, but assessments of restoration effectiveness are rare. The objectives of our study were to assess current acid-precipitation remediation programs in streams of the Allegheny Plateau ecoregion of West Virginia (USA), identify specific attributes that could and could not be fully restored, and quantify temporal trends in ecosystem recovery. We sampled water chemistry, physical habitat, periphyton biomass, and benthic macroinvertebrate and fish community structure in three stream types: acidic (four streams), naturally circumneutral (eight streams), and acidic streams treated with limestone sand (eight streams). We observed no temporal trends in ecosystem recovery in treated streams despite sampling streams that ranged from 2 to 20 years since initial treatment. Our results indicated that the application of limestone sand to acidic streams was effective in fully recovering some characteristics, such as pH, alkalinity, Ca2+, Ca:H ratios, trout biomass and density, and trout reproductive success. However, recovery of many other characteristics was strongly dependent upon spatial proximity to treatment, and still others were never fully recovered. For example, limestone treatment did not restore dissolved aluminum concentrations, macroinvertebrate taxon richness, and total fish biomass to circumneutral reference conditions. Full recovery may not be occurring because treated streams continue to drain acidic watersheds and remain isolated in a network of acidic streams. We propose a revised stream restoration plan for the Allegheny Plateau that includes restoring stream ecosystems as connected networks rather than isolated reaches and recognizes that full recovery of acidified watersheds may not be possible.     

Assessing the toxicity and teratogenicity of pond water in north-central minnesota to amphibians

BACKGROUND: Incidence of amphibian deformities have increased in recent years, especially in the northern region of the United States. While many factors have been proposed as being responsible for generating deformities (e.g., contaminants, ultraviolet radiation [UV], parasites), no single cause has been definitively established. METHODS: To determine whether waterborne chemicals are responsible for amphibian deformities in ponds in north-central Minnesota, we deployed semipermeable membrane devices (SPMDs) in an impacted and a reference site to accumulate lipophilic contaminants. We then exposed native tadpoles (northern leopard frogs; Rana pipiens) to the SPMD extracts combined with two agricultural pesticides (atrazine, carbaryl) at two levels of UV radiation. RESULTS AND DISCUSSION: UV radiation alone caused a slight increase in hatching success and tadpole growth rate. Deformity rate among hatchlings was high following exposure to SPMD extracts from the reference site in the absence of UV, suggesting that chemicals present at this site are broken down by UV to less harmful forms, or become less bioavailable. Conversely, impacted site SPMD extracts caused hatchling deformities only in the presence of UV, suggesting that UV potentiates the teratogenicity of the compounds present there. Impacted site SPMD extracts significantly increased the number of bony triangles among metamorphs, a common deformity observed at this site. The incidence of skin webbings increased significantly with SPMD extracts from both sites as well as with our pesticide control containing atrazine and carbaryl alone. CONCLUSIONS: Higher deformity rates among tadpoles reared in the presence of UV radiation and SPMD extracts from sites where deformities are common indicates a chemical compound (or compounds) in the water at this site may be causing the deformities. RECOMMENDATIONS AND OUTLOOK: It is important to examine the effects of chemical stressors in the presence of other natural stressors (e.g., UV radiation) to gain a better understanding of how multiple stressors work to impact amphibians and amphibian populations.     

Distribution and rate of disappearance of fluorene in pond ecosystems

Fluorene, an energy related polynuclear aromatic hydrocarbon, was applied to several experimental pond ecosystems to effect concentrations of 0.12, 0.5, 2.0, 5.0, and 10.0 mg/L. Water, benthic sediment, and rooted macrophytes were monitored for fluorene residues for 56 days after application. Most of the fluorene at concentrations greater than its water solubility appeared to sublime from the surface of the ponds. The rate of disappearance of fluorene from the water decreased as the application rate increased. This reduction was linked to high concentrations and a flux of fluorene from benthic sediments, macrophytes, and pond surfaces to water columns. Several parameters of photosynthetic primary production were statistically linked to the accelerated disappearance of fluorene from the water.     

Uptake rate constants and partition coefficients for vapor phase organic chemicals using semipermeable membrane devices (SPMDs)

To fully utilize semipermeable membrane devices (SPMDs) as passive samplers in air monitoring, data are required to accurately estimate airborne concentrations of environmental contaminants. Limited uptake rate constants (k_ua) and no SPMD air partitioning coefficient (K_sa) existed for vapor-phase contaminants. This research was conducted to expand the existing body of kinetic data for SPMD air sampling by determining k_ua and K_sa for a number of airborne contaminants including the chemical classes: polycyclic aromatic hydrocarbons, organochlorine pesticides, brominated diphenyl ethers, phthalate esters, synthetic pyrethroids, and organophosphate/organosulfur pesticides. The k_uas were obtained for 48 of 50 chemicals investigated and ranged from 0.03 to 3.07 m³ g^?1 d^?1. In cases where uptake was approaching equilibrium, K_sas were approximated. K_sa values (no units) were determined or estimated for 48 of the chemicals investigated and ranging from 3.84E+5 to 7.34E+7. This research utilized a test system (United States Patent 6,877,724 B1) which afforded the capability to generate and maintain constant concentrations of vapor-phase chemical mixtures. The test system and experimental design employed gave reproducible results during experimental runs spanning more than two years. This reproducibility was shown by obtaining mean k_ua values (n = 3) of anthracene and p,p′-DDE at 0.96 and 1.57 m³ g^?1 d^?1 with relative standard deviations of 8.4% and 8.6% respectively.