Using exposure biomarkers in children to compare between-child and within-child variance and calculate correlations among siblings for multiple environmental chemicals

Longitudinal measurements of biomarkers for metals, phthalates, environmental tobacco smoke, organochlorine and organophosphate pesticides, polychlorinated biphenyls, and volatile organic compounds were made in blood and/or urine from a stratified, random sample of more than 100 elementary school-aged children living in an inner-city section of Minneapolis. Repeated measures of 31 exposure biomarkers indicate that between-child variance (B-CV) was greater than within-child variance (W-CV) for 8 compounds, B-CV was a significant proportion of total variance for 9 compounds, and variances were homogeneous for 14 compounds. Among siblings living in the same household, positive correlations were observed for biomarker concentrations of polychlorinated biphenyls, organochlorine pesticides, metals, and volatile organic chemicals in blood, and total cotinine in urine. Biologic markers confirm that children from a low-income, ethnically diverse neighborhood experienced concurrent exposure to a variety of hazardous environmental chemicals during their everyday activities. Future monitoring studies should examine the nature and magnitude of children's cumulative exposure to both chemical and non-chemical stressors, especially in disadvantaged populations.

Cumulative risk assessment for combined health effects from chemical and nonchemical stressors

Cumulative risk assessment is a science policy tool for organizing and analyzing information to examine, characterize, and possibly quantify combined threats from multiple environmental stressors. We briefly survey the state of the art regarding cumulative risk assessment, emphasizing challenges and complexities of moving beyond the current focus on chemical mixtures to incorporate nonchemical stressors, such as poverty and discrimination, into the assessment paradigm. Theoretical frameworks for integrating nonchemical stressors into cumulative risk assessments are discussed, the impact of geospatial issues on interpreting results of statistical analyses is described, and four assessment methods are used to illustrate the diversity of current approaches. Prospects for future progress depend on adequate research support as well as development and verification of appropriate analytic frameworks.

Conceptual models for cumulative risk assessment

In the absence of scientific consensus on an appropriate theoretical framework, cumulative risk assessment and related research have relied on speculative conceptual models. We argue for the importance of theoretical backing for such models and discuss 3 relevant theoretical frameworks, each supporting a distinctive "family" of models. Social determinant models postulate that unequal health outcomes are caused by structural inequalities; health disparity models envision social and contextual factors acting through individual behaviors and biological mechanisms; and multiple stressor models incorporate environmental agents, emphasizing the intermediary role of these and other stressors. The conclusion is that more careful reliance on established frameworks will lead directly to improvements in characterizing cumulative risk burdens and accounting for disproportionate adverse health effects.

Biomarker measurements of concurrent exposure to multiple environmental chemicals and chemical classes in children

Concern is mounting that children from disadvantaged, low-income neighborhoods are likely to be both more exposed to chemical hazards and more susceptible to related adverse health effects. This article reports measurements of >75 individual biomarkers spanning 7 chemical/pollutant classes in blood and urine from more than 100 children living in a socioeconomically disadvantaged and ethnically diverse area of south Minneapolis, MN. Results indicate that a significant proportion of children in the study were at the high end of the exposure distribution compared to national reference ranges for a variety of environmental chemicals and/or their metabolites, including phthalates, organochlorine pesticides, organophosphate pesticides, metals, polychlorinated biphenyls, and volatile organic compounds. In addition, levels of cotinine in urine indicate that more than half the children were regularly exposed to environmental tobacco smoke, with the upper 10th percentile exposed to relatively high concentrations.

The role of cumulative risk assessment in decisions about environmental justice

There is strong presumptive evidence that people living in poverty and certain racial and ethnic groups bear a disproportionate burden of environmental health risk. Many have argued that conducting formal assessments of the health risk experienced by affected communities is both unnecessary and counterproductive-that instead of analyzing the situation our efforts should be devoted to fixing obvious problems and rectifying observable wrongs. We contend that formal assessment of cumulative health risks from combined effects of chemical and nonchemical stressors is a valuable tool to aid decision makers in choosing risk management options that are effective, efficient, and equitable. If used properly, cumulative risk assessment need not impair decision makers' discretion, nor should it be used as an excuse for doing nothing in the face of evident harm. Good policy decisions require more than good intentions; they necessitate analysis of risk-related information along with careful consideration of economic issues, ethical and moral principles, legal precedents, political realities, cultural beliefs, societal values, and bureaucratic impediments. Cumulative risk assessment can provide a systematic and impartial means for informing policy decisions about environmental justice.

Henoch-Schönlein purpura and meningococcal B vaccination

The risk of Henoch-Schönlein purpura (HSP) following vaccination with a group B meningococcal vaccine was assessed through active hospital safety monitoring. There was no increase in the relative incidence of HSP within 30 days after vaccination nor recurrence in HSP cases who received one or more further vaccine doses (re-challenge).

BRCA1 gene expression signature predicts for anthracycline-chemosensitivity in triple-negative breast cancer

Abstract #6039

Background: We used a previously published gene expression signature that can identify tumors from BRCA1 mutation carriers to evaluate its predictive value in triple-negative breast cancer as a marker for chemosensitivity to anthracycline-based chemotherapy. We proposed that based on preclinical evidence suggesting that BRCA1-deficient breast cancer cells are sensitive to DNA damaging drugs such as cisplatin and anthracyclines this gene expression profile may identify tumors with anthracycline chemosensitivity. Two previously published studies defined a gene expression signature associated with BRCA1 germline mutation.(1,2) In these studies, sporadic tumors were misclassified as BRCA1 tumors and further analysis revealed methylation of the BRCA1 promoter region and decreased BRCA1 gene expression. This finding suggests the possibility of identifying sporadic tumors with decreased BRCA1 activity.
 Methods: We selected from our database of a locally advanced breast cancer neoadjuvant trial all cases of triple negative breast cancer that received 4 cycles of doxorubicin/cyclophosphamide(AC, 60/200 mg/m2, every 3 weeks) prior to surgery. Pathologic response to chemotherapy was disappearance of all invasive cancer or microscopic residual disease. Tumoral gene expression profile previously obtained using Affymetrix U133A Chip was analyzed for an optimal set of 100 most differentially expressed genes distinguishing BRCA1 and sporadic triple negative tumors according to the previously identified gene signature by van't Veer et al.1 We performed unsupervised clustering to determine if this signature could classify a subtype of triple-negative tumors with "BRCAness" and to test our hypothesis that BRCA1-like tumors are more sensitive to AC. We then performed a supervised analysis to determine the most differentially expressed genes that could prospectively identify triple-negative sporadic tumors with “BRCAness” and tumors from BRCA1 germline carriers that are sensitive to anthracyclines.
 Results: Of the 66 patients enrolled in our neoadjuvant trial, 12 patient's tumors were triple negative and received preoperative AC. By unsupervised clustering, the gene expression pattern associated with BRCA1 cancers subdivided these sporadic cancers in to two groups: Group A(6/7 pathologic responders), and group B(5/5 non-pathologic responders). By supervised analysis, the most differentially overexpressed gene from the BRCA1 profile for AC sensitivity was YWHAH(14-3-3 eta polypeptide), while DKK3(Inhibitor of Wnt and Notch signaling pathway) and RPL23A were most overexpressed in all cases with adriamycin-resistance(p<0.01).
 Discussion: Triple negative sporadic breast cancer displaying “BRCAness” appear to be sensitive to AC chemotherapy. YWHAH, DKK3, and RPL23A are differentially expressed in anthracycline-sensitive versus resistant tumors. These three genes can potentially identify triple-negative breast cancers that exhibit “BRCAness” and sensitivity to DNA-damaging chemotherapy such as cisplatin, anthracycline, or PARP inhibitors.

Citation Information: Cancer Res 2009;69(2 Suppl):Abstract nr 6039.

Cumulative cancer risk from air pollution in Houston: disparities in risk burden and social disadvantage

Air toxics are of particular concern in Greater Houston, home to one of the world's largest petrochemical complexes and a quarter ofthe nation's refining capacity. Much of this complex lies along a navigable ship channel that flows 50 miles from east of the central business district through Galveston Bay and into the Gulf of Mexico. Numerous communities, including both poor and affluent neighborhoods, are located in close proximity to the 200 facilities along this channel. Our aim is to examine the spatial distribution of cumulative, air-pollution-related cancer risks in Houston and Harris County, with particular emphasis on identifying ethnic, economic, and social disparities. We employ exposure estimates from NATA-1999 and census data to assess whether the cumulative cancer risks from air toxics in Houston (and Harris County) fall disproportionately on certain ethnicities and on the socially and economically disadvantaged. The cancer risk burden across Harris County census tracts increases with the proportion of residents who are Hispanic and with key indicators of relative social disadvantage. Aggregate disadvantage grows at each higher level of cancer risk. The highest cancer risk in Harris County is concentrated along a corridor flanking the ship channel. These high-risk neighborhoods, however, vary markedly in relative disadvantage, as well as in emission source mix. Much of the risk they face appears to be driven by only a few hazardous air pollutants. Results provide evidence of risk disparities from hazardous air pollution based on ethnicity and social disadvantage. At the highest levels of risk the pattern is more complex, arguing for a neighborhood level of analysis, especially when proximity to high-emissions industries is a substantial contributor to cumulative cancer risk.

Relationships between personal, indoor, and outdoor exposures to trace elements in PM(2.5)

Twenty-four hour average fine particle concentrations of 23 trace elements (TEs) were measured concurrently in (a) ambient air in three urban neighborhoods (Battle Creek-BCK; East St. Paul-ESP; and Phillips-PHI), (b) air inside residences of participants, and (c) personal air near the breathing zone of healthy, non-smoking adults. The outdoor (O), indoor (I), and personal (P) samples were collected in the Minneapolis/St. Paul metropolitan area over three seasons (Spring, Summer, Fall) using either the federal reference (O) or inertial impactor (I,P) inlets to collect PM(2.5). In addition to descriptive statistics, a hierarchical, mixed-effects statistical model was used to estimate the mutually adjusted effects of monitor location, community, and season on mean differences between monitoring locations while accounting for within-subject and within-monitoring period correlation. The relationships among P, I, and O concentrations varied across TEs. The O concentrations were usually higher than P or I for elements like Ca and Al that originate mainly from entrained crustal material, while P concentrations were often highest for other elements with non-crustal sources. Unadjusted mixed model results demonstrated that O monitors more frequently underestimated than overestimated P TE exposures for elements associated with non-crustal sources. This finding was true even though the O TE measurements were taken in the same neighborhoods as the P and I measurements. Further adjustment for community or season effects in the mixed models reduced the number of significant O-P and O-I differences compared to unadjusted models, but still indicated a tendency for underestimation of personal and indoor TE exposures by central site monitors, particularly in the PHI community. These results indicate that community and season are important covariates for developing long term TE exposure estimates, and that personal exposure to trace elements in PM(2.5) is likely to be underestimated by outdoor central site monitors.

Comparative assessment of air pollution-related health risks in Houston

BACKGROUND

Airborne emissions from numerous point, area, and mobile sources, along with stagnant meteorologic conditions, contribute to frequent episodes of elevated air pollution in Houston, Texas. To address this problem, decision makers must set priorities among thousands of individual air pollutants as they formulate effective and efficient mitigation strategies.

OBJECTIVES

Our aim was to compare and rank relative health risks of 179 air pollutants in Houston using an evidence-based approach supplemented by the expert judgment of a panel of academic scientists.

METHODS

Annual-average ambient concentrations by census tract were estimated from the U.S. Environmental Protection Agency's National-scale Air Toxics Assessment and augmented with measured levels from the Houston monitoring network. Each substance was assigned to one of five risk categories (definite, probable, possible, unlikely, uncertain) based on how measured or monitored concentrations translated into comparative risk estimates. We used established unit risk estimates for carcinogens and/or chronic reference values for noncarcinogens to set thresholds for each category. Assignment to an initial risk category was adjusted, as necessary, based on expert judgment about the quality and quantity of information available.

RESULTS

Of the 179 substances examined, 12 (6.7%) were deemed definite risks, 9 (5.0%) probable risks, 24 (13.4%) possible risks, 16 (8.9%) unlikely risks, and 118 (65.9%) uncertain risks.

CONCLUSIONS

Risk-based priority setting is an important step in the development of cost-effective solutions to Houston's air pollution problem.

Characteristics of a high-risk minority population

21141

Background: Black and Hispanic breast cancer patients have a worse outcome when compared to Caucasians. This could be due to socioeconomic, cultural or biologic factors. We hypothesized that host and tumor biologic characteristics associated with a poor outcome may be found more often in minority women. Methods: Race/ethnicity, menopausal status, tumor histological features, and patient characteristics including age and body mass index (BMI) were reviewed from a prospective neoadjuvant trial of docetaxel vs. doxorubicin/cyclophosphamide at Baylor College of Medicine Breast Center, from September 2002 to September 2006. The data were analyzed using Chi-square and Fisher's exact tests, while the Kruskal-Wallis method was used to analyze BMI. Results: Of the 167 patients, 63% (n=105) were Caucasian, 15% (n=26) were Hispanic and 22% (n=36) were Black. The mean age was 47.6 years (range: 30–72). Fifty-nine percent were premenopausal. Overall, mean BMI was 29, with Caucasians having a mean BMI of 27.5, Hispanics with 29.8 and Blacks with a BMI of 34.6 (P<0.001). Sixty-five percent of the Caucasians and 58% of Hispanics were ER+ or PR+ versus 44% of Blacks (P=0.09). Sixteen percent of Caucasians were HER-2 positive compared to 4% of Hispanics and 9% of Blacks (p=0.25). In addition, 22% of Caucasians and 38% of Hispanics were ER-, PR-, HER-2- compared to 50% of tumors from Blacks (p=0.007). There was a trend linking BMI and triple negative status in breast cancers, which did not achieve statistical significance (p=0.21). Conclusion: In this study we found that black and Hispanic women were more likely to be obese and have ER-, PR-, HER-2- tumor phenotypes, both of which have been associated with poorer outcomes. Ongoing studies are being performed to elucidate the link between clinical and biological characteristics and understand the underlying molecular mechanisms associated with these findings.

No significant financial relationships to disclose.

If cumulative risk assessment is the answer, what is the question?

Cumulative risk refers to the combined threats from exposure via all relevant routes to multiple stressors including biological, chemical, physical, and psychosocial entities. Cumulative risk assessment is a tool for organizing and analyzing information to examine, characterize, and possibly quantify the combined adverse effects on human health or ecologic resources from multiple environmental stressors. The U.S. Environmental Protection Agency (EPA) has initiated a long-term effort to develop future guidelines for cumulative risk assessment, including publication in 2003 of a framework that describes important features of the process and discusses theoretical issues, technical matters, and key definitions. The framework divides the process of cumulative risk assessment into three interrelated phases: a) planning, scoping, and problem formulation; b) analysis; and c) interpretation and risk characterization. It also discusses the additional complexities introduced by attempts to analyze cumulative risks from multiple stressors and describes some of the theoretical approaches that can be used. The development of guidelines for cumulative risk assessment is an essential element in the transition of the U.S. EPA risk assessment methodology from a narrow focus on a single stressor, end point, source, pathway, and exposure route to a broader, more holistic approach involving analysis of combined effects of cumulative exposure to multiple stressors via all relevant sources, pathways, and routes.

Assessing cumulative health risks from exposure to environmental mixtures - three fundamental questions

Differential exposure to mixtures of environmental agents, including biological, chemical, physical, and psychosocial stressors, can contribute to increased vulnerability of human populations and ecologic systems. Cumulative risk assessment is a tool for organizing and analyzing information to evaluate the probability and seriousness of harmful effects caused by either simultaneous and/or sequential exposure to multiple environmental stressors. In this article we focus on elucidating key challenges that must be addressed to determine whether and to what degree differential exposure to environmental mixtures contributes to increased vulnerability of exposed populations. In particular, the emphasis is on examining three fundamental and interrelated questions that must be addressed as part of the process to assess cumulative risk: a) Which mixtures are most important from a public health perspective? and b) What is the nature (i.e., duration, frequency, timing) and magnitude (i.e., exposure concentration and dose) of relevant cumulative exposures for the population of interest? c) What is the mechanism (e.g., toxicokinetic or toxicodynamic) and consequence (e.g., additive, less than additive, more than additive) of the mixture's interactive effects on exposed populations? The focus is primarily on human health effects from chemical mixtures, and the goal is to reinforce the need for improved assessment of cumulative exposure and better understanding of the biological mechanisms that determine toxicologic interactions among mixture constituents.

Serum leptin concentration, adiposity, and body fat distribution in Mexican-Americans

BACKGROUND

Leptin is strongly associated with adiposity and few studies have investigated its role in Mexican-Americans. The aims of this study were to examine the association of serum leptin concentration with adiposity and body fat distribution in Mexican-Americans and to develop a predictive model of serum leptin concentration for this ethnic group.

METHODS

Three hundred fifty-two college students (242 women, 110 men; age 18-30 years) were evaluated in this cross-sectional study. Body fat content was assessed using bioelectrical impedance analysis. Correlation between serum leptin levels and several markers of adiposity and body fat distribution were examined in both men and women. Multiple regression analysis was performed to create the predictive model.

RESULTS

Women had higher serum leptin concentrations than men for the same levels of adiposity. After controlling for gender and body fat, only fat mass (FM) expressed in kg, was significantly correlated with serum leptin concentration in men (partial rho = 0.811, p <0.001), whereas body mass index (BMI), hip circumference (HC), and FM expressed in kg, were significantly correlated with serum leptin concentration in women (partial rho = 0.214, p <0.001; partial rho = 0.201, p <0.01; and partial rho = 0.818, p <0.001, respectively). Percent body fat (PBF) was the only significant predictor of serum leptin concentration among men, explaining 42% of the variance in serum leptin concentration. In addition to PBF, waist circumference (WC) and HC were significant predictors of serum leptin concentration among women explaining 65% of the variance in serum leptin concentration.

CONCLUSIONS

Serum leptin concentration is a function of adiposity as determined by PBF in both Mexican-American men and women. HC and WC are associated with serum leptin concentration in Mexican-American women but not in men. BMI alone should not be used in evaluating the association of serum leptin concentration with body fatness in Mexican-Americans.

Estimating volatile organic compound concentrations in selected microenvironments using time-activity and personal exposure data

Repeated measures of personal exposure to 14 volatile organic compounds (VOC) were obtained over 3 seasons for 70 healthy, nonsmoking adults living in Minneapolis-St. Paul. Matched data were also available for participants' time-activity patterns, and measured VOC concentrations outdoors in the community and indoors in residences. A novel modeling approach employing hierarchical Bayesian techniques was used to estimate VOC concentrations (posterior mode) and variability (credible intervals) in five microenvironments: (1) indoors at home; (2) indoors at work/school; (3) indoors in other locations; (4) outdoors in any location; and (5) in transit. Estimated concentrations tended to be highest in "other" indoor microenvironments (e.g., grocery stores, restaurants, shopping malls), intermediate in the indoor work/school and residential microenvironments, and lowest in the outside and in-transit microenvironments. Model estimates for all 14 VOC were reasonable approximations of measured median concentrations in the indoor residential microenvironment. The largest predicted contributor to cumulative (2-day) personal exposure for all 14 VOC was the indoor residential environment. Model-based results suggest that indoors-at-work/school and indoors-at-other-location microenvironments were the second or third largest contributors for all VOC, while the outside-in-any-location and in-transit microenvironments appeared to contribute negligibly to cumulative personal exposure. Results from a mixed-effects model indicate that being in or near a garage increased personal exposure to o-xylene, m/p-xylene, benzene, ethylbenzene, and toluene, and leaving windows and doors at home open for 6 h or more decreased personal exposure to 13 of 14 VOC, all except trichloroethylene.

Asthma, atopy, and lung function among racially diverse, poor inner-urban Minneapolis schoolchildren

As part of an assessment of schoolchildren's environmental exposures and health, a probability sample of 136 children from diverse racial/ethnic backgrounds was drawn from grades 2-5 of two inner-urban Minneapolis schools (Whittier, Lyndale). Questionnaires were administered to a parent/guardian; blood samples for IgE and lung function tests were obtained. Overall adjusted rates for lifetime asthma (15.4%; 95%CI 9.3-21.5%), asthma in the last 12 months (13.6%; 7.8-19.4%), and current asthma medication use (10.5%; 5.3-15.7%) were higher than reported US national rates. Adjusted rates for lifetime physician-diagnosed asthma differed significantly among racial/ethnic groups (P<0.01): African-Americans (25.9%), White/Others (25.8%), Hispanics (9.3%), Somalis (1.8%), Asians (0%). Corresponding rates for atopy (total IgE>100 IU/mL or an allergen-specific IgE>0.35 IU/mL) were: African-Americans (66.6%), White/Others (100%), Hispanics (77.2%), Somalis (78.1%), Asians (81.8%). Lung function (FEV1, FVC) was analyzed by linear regression using log-transformed data: significant race-specific differences in lung function were found relative to White/Others (P<0.001 for each racial/ethnic group): African-Americans (FEV1 -16.5%, FVC -16.9%), Somalis (-22.7%, -26.8%), Hispanics (-12.2%, -11.4%) and Asians (-11.1%, -12.4%). Females had significantly lower FEV1 (-8.8%) and FVC (-11.0%) than males. An unexplained, significant difference in children's lung function was found between the two schools. A history of physician-diagnosed asthma was not associated with decreased lung function. Factors other than poverty, inner-urban living, and IgE levels (atopy) need to be considered in the development of childhood asthma.

Gene expression profiles in formalin-fixed, paraffin-embedded (FFPE) core biopsies predict docetaxel chemosensitivity

538

Background: Docetaxel has one of the highest response rates as a single agent in breast cancer, but de novo resistance is frequent. Previously, we had identified a 92-gene expression pattern that predicted response to neoadjuvant docetaxel. Other studies have validated that a high Recurrence Score (RS) by the 21-gene RT-PCR assay is predictive of worse prognosis (Paik, NEJM 2004) but better response to chemotherapy (Gianni, JCO 2005). We investigated whether tumor gene expression of these 21 genes and other candidate genes can predict response to docetaxel. Methods: Core biopsies from 97 patients were obtained before treatment with neoadjuvant docetaxel (4 cycles, 100 mg/m2 q3 weeks). Baseline and post-treatment measurements of the primary breast cancers were recorded. Three 10-micron FFPE sections were submitted for quantitative RT-PCR assays of 192 genes that were selected from our previous work and the literature. Results: Of the 97 patients, 81 (84%) had sufficient invasive breast cancer, 80 (82%) had sufficient RNA for assay of 192 genes, and 72 (74%) had clinical response data. Mean age was 48.5 years, and the median tumor size was 6 cm. Clinical complete responses (CR) by RECIST were observed in 12 (17%), partial responses in 41 (57%), stable disease in 17 (24%), and progressive disease in 2 patients (3%). The concordance of IHC and RT-PCR results was >80% for ER, PgR, and HER2. By univariate logistic regression, a significant correlation (p<0.05) between gene expression and CR was observed for 14 genes. Notably, CYBA-1 involved in mitochondrial metabolism, identified by gene expression profiling, significantly predicted CR (p=0.006). CR was associated with lower expression of the ER gene group and higher expression of the proliferation gene group. Multivariate analysis indicated that panels of genes better predictors of docetaxel response. Of note, CR was more likely with high RS and less likely with a low RS (p=0.008). Conclusion: We have established molecular profiles for breast cancers either responding or not responding to neoadjuvant docetaxel. This technology is a potential predictive test for docetaxel sensitivity by using small amounts of FFPE material, and may reduce unnecessary treatment, toxicity, and cost for breast cancer patients.

[Table: see text]

Limited impact of tamoxifen following dose-intensive L-FAC multimodality therapy of breast cancer

10741

Background: Front-line dose-intensive L-FAC has demonstrated a favorable 5-year relapse free survival pattern (ASCO 2004 #739). Tamoxifen was given for 5 years to ER+ patients after L-FAC completion. We evaluated the impact of adding tamoxifen to L-FAC. By design, this pilot study excluded low-risk patients not candidates for chemotherapy. Methods: 109 breast cancer patients were enrolled (4 excluded due to treatment violations) from 6/1989 to 1/2003: 20 Stage I (S), 52 S-II, 22 S-III, for a total of 94 patients. 11 S-IV patients were excluded from survival analysis. Adverse tumor presentations included: ER- 49, PgR- 60, P53+ 24, non-diploid 39, histological grade III 37, CerbB2+ 33. L-FAC included 72 hour (h) iv infusion 400mg/m2/day (d) 5-fluorouracil (F) modulated by iv bolus 200mg/m2/d X3 leucovorin (L), concomitantly with 24h iv d1 600–1000mg/m2 cyclophosphamide (C), 48h iv d2 + d3 60mg/m2 doxorubicin (A). S-I and S-II were given 6 courses and 8 for S-III. Increasing A + C dose level and/or shortening treatment intervals < 3 weeks with growth factors provided intensification. 40 patients received tamoxifen. Results: At a median follow-up of 74 months (range 9–214), 73 (78%) are alive (1 with relapse). Relapse free survival was: S-I 95%, S-II 81%, S-III 78%. At average course intervals of 18 days, dose intensity A/C mg/m2/wk was 24.2 / 335.4 with evidence of WHO grade III/IV stomatitis in 43%, neutropenia 59%, cumulative thrombocytopenia 50%, hand-foot syndrome 32% of patients. Aside from delayed relapse associated with tamoxifen, relapse-free survival >82 months was similar with and without tamoxifen. No relapse was observed after >53 months in ER- tumors despite showing higher frequency of adverse tumor risk factors. Conclusion: The impact of adding tamoxifen appears quite limited in a patient population with adverse tumor presentation treated with dose-intensive L-FAC.

No significant financial relationships to disclose.

Conventional and toxicogenomic assessment of the acute pulmonary damage induced by the instillation of Cardiff PM10 into the rat lung

There is strong epidemiological evidence of association between PM10 (particulate matter with an aerodynamic diameter less than or equal to 10 microm) and adverse health outcomes including death and increased hospital admissions for cardiopulmonary conditions. Ambient PM10 surrogates such as diesel exhaust particles (DEP), a common component of UK PM10 have been shown to induce lung inflammation in both humans and rodents. To date, few studies have reported on the toxicological response of UK PM10 in experimental animals. This study examines the pulmonary toxicological responses in male Sprague Dawley rats following the intratracheal instillation of Cardiff urban PM10. A mild but significant change in lung permeability was observed in the lung post-instillation of a high (10 mg) dose of the whole PM10 as adjudged by increases in lung to body weight ratio and total acellular lavage protein. Such effects were less marked following instillation of a water-soluble fraction (80% of the total mass) but histological examination showed that lung capillaries were swollen in size with this treatment. In conclusion, conventional toxicological, histological and toxicogenomic studies have indicated that Cardiff PM10 exhibits low bioreactivity in the form of mild permeability changes. Differential gene expression was observed when the lung was treated with whole PM10, containing durable particles, in comparison with the water-soluble fraction of PM10 that was devoid of particles. Such changes were linked to different histopathological events within the lung.

Using biologic markers in blood to assess exposure to multiple environmental chemicals for inner-city children 3-6 years of age

We assessed concurrent exposure to a mixture of > 50 environmental chemicals by measuring the chemicals or their metabolites in the blood of 43 ethnically diverse children (3-6 years of age) from a socioeconomically disadvantaged neighborhood in Minneapolis. Over a 2-year period, additional samples were collected every 6-12 months from as many children as possible. We analyzed blood samples for 11 volatile organic compounds (VOCs), 2 heavy metals (lead and mercury, 11 organochlorine (OC) pesticides or related compounds, and 30 polychlorinated biphenyl (PCB) congeners. The evidence suggests that numerous VOCs originated from common sources, as did many PCBs. Longitudinal measurements indicate that between-child variance was greater than within-child variance for two VOCs (benzene, toluene), for both heavy metals (Pb, Hg), for all detectable OC pesticides, and for 15 of the measured PCB congeners (74, 99, 101, 118, 138-158, 146, 153, 156, 170, 178, 180, 187, 189, 194, 195). Despite the relatively small sample size, highest measured blood levels of 1,4-dichlorobenzene, styrene, m-/p-xylene, Pb, Hg, heptachlor epoxide, oxychlordane, dichlorodiphenyldichloroethene (p,p -DDE), trans-nonachlor, and PCB congeners 74, 99, 105, 118, 138, 146, 153, 156, 170, and 180 were comparable with or higher than 95th percentile measurements of older children and adults from national surveys. Results demonstrate that cumulative exposures to multiple environmental carcinogens and neurotoxins can be comparatively high for children from a poor inner-city neighborhood.

Indoor air quality in two urban elementary schools--measurements of airborne fungi, carpet allergens, CO2, temperature, and relative humidity

This article presents measurements of biological contaminants in two elementary schools that serve inner city minority populations. One of the schools is an older building; the other is newer and was designed to minimize indoor air quality problems. Measurements were obtained for airborne fungi, carpet loadings of dust mite allergens, cockroach allergens, cat allergens, and carpet fungi. Carbon dioxide concentrations, temperature, and relative humidity were also measured. Each of these measurements was made in five classrooms in each school over three seasons--fall, winter, and spring. We compared the indoor environments at the two schools and examined the variability in measured parameters between and within schools and across seasons. A fixed-effects, nested analysis was performed to determine the effect of school, season, and room-within-school, as well as CO2, temperature and relative humidity. The levels of all measured parameters were comparable for the two schools. Carpet culturable fungal concentrations and cat allergen levels in the newer school started and remained higher than in the older school over the study period. Cockroach allergen levels in some areas were very high in the newer school and declined over the study period to levels lower than the older school. Dust mite allergen and culturable fungal concentrations in both schools were relatively low compared with benchmark values. The daily averages for temperature and relative humidity frequently did not meet ASHRAE guidelines in either school, which suggests that proper HVAC and general building operation and maintenance procedures are at least as important as proper design and construction for adequate indoor air quality. The results show that for fungi and cat allergens, the school environment can be an important exposure source for children.

Comparison of recruitment, retention, and compliance results for three children's exposure monitoring studies

The School Health Initiative: Environment, Learning, Disease (SHIELD) study, the Minnesota Children's Pesticide Exposure Study (MNCPES), and the National Cooperative Inner-City Asthma Study (NCICAS) are three of the most intensive and invasive exposure-monitoring projects ever undertaken in children. An intrinsic facet of each study was the need to recruit children and their families, retain them for the duration of the project, and ensure that they completed monitoring protocols successfully. All of the studies used fiscal incentives to encourage participation, retention, and compliance. Recruitment rates varied from 40% in MNCPES, to 57% in SHIELD, to 64% in NCICAS, while retention rates varied from 85% in SHIELD, to 94% in MNCPES, to 95% in NCICAS. Rates of compliance with exposure sampling procedures were typically >80% for each study. For example, > or =85% of the enrolled children provided all requested urine samples (1 for NCICAS, 2 for SHIELD, 3 for MNCPES), and 82% of the children in SHIELD provided two out of two blood samples (optional in MNCPES and NCICAS). However, compliance rates were substantially lower (34% SHIELD, 40% NCICAS, not applicable to MNCPES) for the more complex and time-consuming protocol used to collect peak flow data. Overall, results demonstrate that it is practical and affordable to conduct demanding exposure-monitoring studies in children, including children from poor minority communities.