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BACKGROUND: Tranexamic acid (TXA) has been shown to reduce mortality from severe haemorrhage. Although recent data suggest that TXA has anti-inflammatory properties, few analyses have investigated the impact of TXA on infectious complications in injured patients. The aim was to examine the association between TXA administration and infection risk among injured military personnel. METHODS: Patients who received TXA were matched by Injury Severity Score with patients who did not receive TXA. Conditional logistic regression was used to examine risk factors associated with infections within 30 days. A Cox proportional analysis evaluated risk factors in a time-to-first-infection model. RESULTS: A total of 335 TXA recipients were matched with 626 patients who did not receive TXA. A greater proportion of TXA recipients had an infection compared with the comparator group (P < 0·001). Univariable analysis estimated an unadjusted odds ratio (OR) of 2·47 (95 per cent c.i. 1·81 to 3·36) for the association between TXA and infection risk; however, TXA administration was not significant in multivariable analysis (OR 1·27, 0·85 to 1·91). Blast injuries, intensive care unit (ICU) admission, and receipt of 10 units or more of blood within 24 h after injury were independently associated with infection risk. The Cox proportional model confirmed the association with ICU admission and blood transfusion. Traumatic amputations were also significantly associated with a reduced time to first infection. CONCLUSION: In life-threatening military injuries matched for injury severity, TXA recipients did not have a higher risk of having infections nor was the time to develop infections shorter than in non-recipients. Extent of blood loss, blast injuries, extremity amputations and ICU stay were associated with infection.

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The emergence of invasive fungal wound infections (IFIs) in combat casualties led to development of a combat trauma-specific IFI case definition and classification. Prospective data were collected from 1133 US military personnel injured in Afghanistan (June 2009-August 2011). The IFI rates ranged from 0·2% to 11·7% among ward and intensive care unit admissions, respectively (6·8% overall). Seventy-seven IFI cases were classified as proven/probable (n = 54) and possible/unclassifiable (n = 23) and compared in a case-case analysis. There was no difference in clinical characteristics between the proven/probable and possible/unclassifiable cases. Possible IFI cases had shorter time to diagnosis (P = 0·02) and initiation of antifungal therapy (P = 0·05) and fewer operative visits (P = 0·002) compared to proven/probable cases, but clinical outcomes were similar between the groups. Although the trauma-related IFI classification scheme did not provide prognostic information, it is an effective tool for clinical and epidemiological surveillance and research.

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Here, we report the screening of 332 new accessions of 11 different wild oat (Avena) species from the United States Department of Agriculture National Small Grains Collection in Aberdeen, ID, for resistance to crown rust disease, caused by Puccinia coronata f. sp. avenae. This collection originated from Morocco and includes Avena agadiriana, A. atlantica, A. barbata, A. damascena, A. eriantha, A. hirtula, A. longiglumis, A. magna, A. murphyi, A. sterilis, and A. wiestii. After screening this collection with a highly diverse population of P. coronata f. sp. avenae, 164 accessions (49%) were rated moderately resistant to resistant in the preliminary screen at the seedling stage and 181 accessions (55%) rated moderately resistant to highly resistant in the adult plant stage. Although none of the accessions showed a highly resistant response consistently in the seedling stage, 20 accessions did display a highly resistant response in the adult plant stage. Both seedling as well as adult plant resistance was found in 150 (45%) of the accessions. Virulence in P. coronata has been reported to all resistance genes currently being used in North American oat cultivars. The new resistance sources presented here are potentially new sources for future breeding. The resistance found in 52 accessions of A. magna and A. murphyi with the AACC genome is especially valuable because these should be relatively easy to transfer into hexaploid A. sativa.

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The use of race-specific seedling genes for resistance is the primary means of controlling crown rust of oat (Puccinia coronata f. sp. avenae) in the United States. To better utilize those resistance genes, knowledge of the occurrence and frequency of corresponding virulence in the population of P. coronata f. sp. avenae in the United States is essential. In total, 571 single-pustule isolates of oat crown rust were collected from cultivated and wild oat (Avena sativa and A. fatua, respectively) in the major oat production areas of the United States from 2006 through 2009. They were tested for virulence on seedlings of 31 differential oat lines in the greenhouse. In all, 201 races were found among the 357 isolates from the spring oat region of the north-central United States, and 140 races were found among 214 isolates from the southern winter oat region. The crown rust populations from the winter and spring oat regions were clearly differentiated from one another, differing in the frequency of virulence for 24 of the 31 differentials. Some virulence associations previously reported in the U.S. oat crown rust population were also found in both regions in this survey, even when the dataset was clone corrected. Associations between virulence to the Pc genes were predominately positive in both regions but both positive and negative associations occurred more frequently in the winter oat region, where sexual reproduction does not occur. Some of the virulence diversity in the oat crown rust population in the United States can be related to the deployment of resistance genes in commercial oat cultivars and virulence associations existing in the oat crown rust population. When data from a previous report covering 2001 through 2005 is combined with data reported in this article, the mean virulence of the U.S. populations of crown rust continued to increase from 2001 to 2009. Virulence to Pc38, Pc39, Pc45, Pc48, Pc52, Pc55, Pc56, Pc57, Pc59, Pc62, Pc63, Pc64, Pc68, and Pc96 significantly increased in one or both regions during this time period. No significant declines in virulence frequency were found in either region. Genes for crown rust resistance derived from A. sterilis appear to be as rapidly defeated as has happened to Pc genes from A. sativa. There is an urgent need to find additional sources of effective resistance to P. coronata f. sp. avenae and introgress it into adapted oat cultivars.

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Crown rust is the most damaging disease of cultivated oat (Avena sativa) and genetic resistance is the primary means of controlling the disease. Quantitative trait loci (QTL) with major and minor effects have been identified in Ogle1040 and TAM O-301 (most notably, Pc58 and PcNQMG/LGCG from TAM O-301 and OT-27 from Ogle1040) through single-isolate greenhouse and field tests. To map loci and determine the effectiveness of previously identified QTL against naturally occurring pathogen populations in highly disease-conducive environments, the Ogle/TAM O-301 (OT) recombinant inbred line (RIL) population was grown in Texas and Louisiana over 2 years and in Manitoba, Canada. The genetic region characterized by the Pc58 resistance gene complex, particularly Pc58a, accounted for most of the diseased leaf area (DLA) and infection type (IT) variance in all five experiments. Additionally, the genetic region characterized by PcNQMG/LGCG accounted for a portion of the IT variance in three experiments. Although no QTL was detected on OT-27 in this study, all the markers on this linkage group were associated (P < 0.0001) with reducing both IT and DLA using single-marker analysis. Screening with 25 Puccinia coronata isolates from six different states indicated that Pc58abc and Pc58a were highly effective, while characterization using F(2) populations derived from OT RILs containing the two main genetic regions responsible for crown rust resistance in TAM O-301 (Pc58 and PcNQMG/LGCG) and a minor QTL in Ogle (OT-27) indicated that Pc58a, in combination with a locus in Ogle1040, provided high levels of resistance to natural races in Texas. This study provides new information and key loci in OT mapping population and may be useful for effective control of crown rust in North America.

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Crown rust (Puccinia coronata f. sp. avenae) is considered the most damaging disease of oat and the use of race-specific seedling (Pc) genes for resistance has been the primary means of control. As these resistance genes from cultivated oat, Avena sativa, and the wild hexaploid animated oat, A. sterilis, were deployed in oat cultivars, corresponding virulence in the U.S. crown rust population increased rapidly, such that the effective lifespan of a resistant cultivar in the United States is now 5 years or less. Introgression of resistance from diploid and tetraploid Avena spp. into hexaploid oat has been difficult due to the difference in ploidy levels and the lack of pairing of homeologous chromosomes between species. The wild tetraploid slender oat, A. barbata, has been a source of powdery mildew and stem rust resistance in cultivated oat but has largely been unexploited for crown rust resistance. A relatively high percentage of A. barbata accessions from the United States Department of Agriculture (USDA) National Small Grains Collection were resistant to a highly diverse crown rust population in recent tests. Tests of 1,099 A. barbata accessions from the Canadian Plant Gene Resources Center not represented in the USDA collection revealed that a similar percentage (11.4%) were at least moderately resistant at the seedling and adult plant stage when tested with a highly diverse bulk inoculum derived from the St. Paul buckthorn nursery. Eighteen accessions were rated as highly resistant or a mix of highly resistant and resistant plants in both seedling and adult plant tests. Three accessions (CN21531 from Italy and CN26271 and CN26305 from Spain) displayed a unique "blotchy" resistant reaction as adult plants. Resistant accessions were found from throughout much of the natural range of A. barbata but the Western Mediterranean and Lebanon had the highest frequency of accessions with broad-spectrum resistance.

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BACKGROUND/OBJECTIVES: Consumption of hydroxypropylmethylcellulose (HPMC), a viscous dietary fiber, lowers total cholesterol (TC) and low-density lipoprotein cholesterol (LDL-C). However, HPMC had not previously been studied in individuals receiving lipid drug therapy. SUBJECTS/METHODS: This randomized, double-blind crossover trial examined the lipid effects of HPMC in subjects with hypercholesterolemia on statin therapy. Men (n=5) and women (n=8) with LDL-C> or =2.59 mmol/l after at least 4 weeks of stable-dose statin therapy, and a mean age of 58.6 years, were enrolled. Subjects received twice daily doses of either 2.5 g HPMC or control, delivered in a lemonade beverage for 4 weeks, then crossed over to receive the opposite treatment for an additional 4 weeks. RESULTS: Mean baseline concentrations of TC, non-high-density lipoprotein cholesterol (non-HDL-C), LDL-C, HDL-C, triglyceride (TG), TC/HDL-C ratio and apolipoprotein (Apo) B were 4.95, 3.63, 3.03, 1.33, 1.30 and 3.89 mmol/l and 1.00 g/l, respectively. HPMC consumption resulted in significantly larger reductions (P<0.01 vs control for all) in TC (-10.9 vs -3.5%), non-HDL-C (-12.8 vs -2.9%), LDL-C (-15.7 vs -5.1%), TC/HDL-C ratio (-5.3 vs +1.3%) and Apo B (-8.7 vs -3.9%). There were no differences between treatments for changes in HDL-C (-5.2 vs -4.3%) or TG (+3.9 vs +8.9%). CONCLUSIONS: These results support the view that HPMC is an effective adjunct to statin therapy for further lowering atherogenic lipids and lipoproteins in men and women with primary hypercholesterolemia.

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The use of race-specific seedling genes for resistance has been the primary means of controlling crown rust of oat (Puccinia coronata). As resistance genes from hexaploid cultivated oat, Avena sativa and, later, the wild hexaploid animated oat, A. sterilis, were deployed in oat cultivars, corresponding virulence in the crown rust population increased rapidly, such that the effective lifespan of a resistant cultivar in the United States is now 5 years or less. Introgression of resistance genes from diploid and tetraploid Avena spp. into hexaploid oat has been difficult due to differences in ploidy levels and the lack of homology of chromosomes between the two species. The wild tetraploid slender oat, A. barbata, has been a source of powdery mildew and stem rust resistance in cultivated oat but has largely been unexploited for crown rust resistance. In total, 359 accessions of A. barbata from the National Small Grains Collection were evaluated in seedling greenhouse tests. Of these accessions, 39% were at least moderately resistant when inoculated with a crown rust race with low virulence (DBBC). When tested further with a highly diverse bulk inoculum from the 2006 and 2007 St. Paul buckthorn nursery, 48 accessions (approximately 13%) were resistant. Many of these accessions were heterogeneous in reaction, but two accessions (PI320588 from Israel and PI337893 from Italy) were highly resistant (immune) and two others (PI337886 from Italy and PI367293 from Spain) consistently produced resistant reactions (chlorotic flecks) in all tests. Resistant accessions were found from throughout much of the natural range of A. barbata. Crosses of some of the better accessions have been made to cultivated oat.

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Crown rust, caused by Puccinia coronata f. sp. avenae is the most important disease of cultivated oat in North America. Numerous race-specific (Pc) genes for crown rust have been found in Avena spp. but this type of resistance has not been durable when used in oat cultivars. Increasing diversity for resistance within a crop by the use of multiline cultivars or varietal mixtures has been proposed as a means of achieving durable resistance to highly variable pathogens such as P. coronata f. sp. avenae. Multiline cv. E77 was evaluated over multiple seasons in the University of Minnesota buckthorn nursery in St. Paul. Buckthorn (Rhamnus cathartica, the alternate host of P. coronata) supports a sexually recombining, highly diverse crown rust population in the St. Paul nursery. Crown rust severity on flag leaves was measured multiple times on E77 and its 10 component lines during grain filling. Single-urediniospore isolates taken from crown rust samples during early stages of the epidemic and at the end of the epidemic were tested for virulence on the 10 component lines of E77 in greenhouse seedling tests. Crown rust development was reduced in E77 compared with the weighted mean of the component lines at all stages of the crown rust epidemics. The mean virulence of single-urediniospore isolates tended to increase late in the epidemic on E77. These data suggest that multilines may select for complex virulence or "super races" and any resistance effect may not be durable.

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In all, 680 single-pustule isolates of the oat crown rust pathogen, Puccinia coronata f. sp. avenae, were collected from cultivated and wild oat (Avena sativa and A. fatua, respectively) in the major oat-production areas of the United States from 2001 through 2005. They were tested for virulence on seedlings of differential oat lines in the greenhouse. In all, 171 races were found among the 357 isolates from the winter oat region of the United States, whereas 212 races were found among 323 isolates from the spring oat region. The crown rust population derived from winter oat in the southern United States was distinct from the spring oat population in the upper Midwest, although there was no virulence unique to either population. Virulence to Pc48 and Pc52 increased significantly in both regions during 2001 to 2005. Virulence to Pc59 increased and virulence to Pc53 decreased in the winter oat region during the same period. Many of the virulence associations previously reported in the U.S. oat crown rust population in the early 1990s also were found in both regions in this survey. Associations between virulence to the Pc genes were predominately positive in both regions; however, both positive and negative associations occurred more frequently in the winter oat region. Much of the virulence diversity in the oat crown rust population in the United States can be related to the deployment of resistance genes in commercial oat cultivars and virulence associations existing in the oat crown rust population. The mean virulence of the U.S. populations of crown rust continued to increase from 2001 to 2005. Genes for crown rust resistance derived from A. sterilis appear to be rapidly defeated, as has happened to Pc genes from A. sativa.

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The intermated B73 x Mo17 (IBM) population, an advanced intercross recombinant inbred line population derived from a cross between the maize lines B73 (susceptible) and Mo17 (resistant), was evaluated in four environments for resistance to southern leaf blight (SLB) disease caused by Cochliobolus heterostrophus race O. Two environments were artificially inoculated, while two were not inoculated and consequently had substantially lower disease pressure. Four common SLB resistance quantitative trait loci (QTL) were identified in all environments, two in bin 3.04 and one each in bins 1.10 and 8.02/3. There was no significant correlation between disease resistance and days to anthesis. A direct comparison was made between SLB QTL detected in two populations, independently derived from the same parental cross: the IBM advanced intercross population and a conventional recombinant inbred line population. Several QTL for SLB resistance were detected in both populations, with the IBM providing between 5 and, in one case, 50 times greater mapping resolution.

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ABSTRACT Setosphaeria turcica causes northern leaf blight, an economically important disease of maize throughout the world. Survey collections of S. turcica isolates from 1974 to 1994 provided a unique opportunity to examine temporal diversity in the eastern United States. Two hundred forty-two isolates of S. turcica from maize were studied with random amplified polymorphic DNA (RAPD) markers, mating type, and virulence on maize differential inbred lines with known Ht resistance genes to examine changes over time. One hundred forty-nine RAPD haplotypes were identified. Nearly 20% of haplotypes recurred in more than one year. Race 0 isolates declined in frequency from 83% in 1974 to near 50% in the 1990s, most likely in response to the widespread deployment of Ht1 in commercial maize hybrids. Races 23 and 23N were present in the collection at low levels throughout the study period and were also found among isolates from Virginia in 1957. The frequency of MAT1-2 isolates increased sharply after 1979 and was associated with the emergence of race 1 during the same period. RAPD markers were used to investigate the genetic diversity among a subset of isolates collected in the United States from 1976 to 1982, the period in which this dramatic shift in race frequency occurred. Multilocus haplotypes were not exclusively associated with known races of S. turcica. Based on shared haplotypes and cluster analysis, race 1 isolates share greater similarity with race 0 than with 23 or 23N isolates, indicating race 1 probably evolved from multiple lineages of race 0. Sorghum spp.-infecting isolates share greater similarity with one another than with maize-infecting isolates and represent a distinct subgroup.

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A synthetic population of maize (Zea mays) was created from five inbred lines of varying levels of partial resistance to northern leaf blight (NLB). This synthetic was subjected to three cycles of recurrent phenotypic selection with pollen control for either increased latent period or decreased lesion length. A selection intensity of ca. 10% was used in each selection cycle. The original synthetic and three advanced selection cycles for each of the two components of partial resistance were evaluated in field trials in the summers of 1999 and 2001, and in greenhouse trials. Selection for increased latent period was more effective in improving resistance to NLB (20 to 27% gain/cycle) (as measured by area under the disease progress curve [AUDPC]) than was selection for decreased lesion length (14 to 18% gain/cycle). Responses in AUDPC to selection for either component of resistance were linear in the 1999 field trial, but were quadratic (decreased response in advanced cycles) in the 2001 trial. Selection for increased latent period in the field resulted in a 0.6-day increase in latent period per selection cycle when measured in the greenhouse and a 2-day increase per selection cycle when measured in the field. Selection for decreased lesion length in the field did not significantly alter latent period in the greenhouse. These results support using selection for increased latent period as an effective means of improving partial resistance to NLB in maize populations. Decreased lesion length was more difficult to measure and selection based on this criterion was less effective in improving partial resistance.

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ABSTRACT A set of 192 maize recombinant inbred lines (RILs), derived from a cross between the inbred lines Mo17 and B73, were evaluated as 3-week-old seedlings in the greenhouse for resistance to southern leaf blight, caused by Cochliobolus heterostrophus race O. Six significant (LOD >3.1) quantitative trait loci (QTL) were identified for disease resistance, located on chromosomes 1, 2, 3, 6, 7, and 8. Results were compared with a previous study that had used the same RIL population and pathogen isolate, but had examined resistance in mature rather than juvenile plants. There was a very weak but significant correlation between the overall resistance phenotypes of the RILs scored as mature and juvenile plants. Two QTL were found in similar positions on chromosomes 1 and 3 at both growth stages. Other QTL were specific to one growth stage or the other. Twenty-three of these RILs, together with the parental lines, were inoculated in the greenhouse with four C. heterostrophus isolates. Results indicated that the quantitative resistance observed was largely isolate non-specific.

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The ability of Phaeosphaeria leaf spot (PLS) to reduce yields of maize was evaluated over two winter growing seasons in southern Florida. Nine commercial maize hybrids, varying in reaction to PLS, were planted in a split-plot design with hybrids as whole plots and inoculated versus uninoculated treatments as subplots. The most susceptible hybrid, Pioneer brand 3489, sustained a significant reduction in grain yield (11 to 13%) and 400-kernel weight (5 to 10%) in the trials. Regression analyses indicated that grain yields and 400-kernel weights were reduced 0.23 and 0.16%, respectively, for each percent increase in PLS severity at the mid-dent stage. Because most U.S. maize hybrids are resistant, and PLS develops late in the grain-filling period, its potential to cause substantial losses in the United States appears limited at this time.

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Phaeosphaeria leaf spot (PLS) is a potentially important disease of maize (Zea mays) that has appeared in winter breeding nurseries in southern Florida. Inbred lines related to B73 are particularly susceptible to Phaeosphaeria leaf spot, whereas inbreds related to Mo17 are highly resistant. A previous study of the inheritance of resistance to Phaeosphaeria leaf spot in the cross B73 × Mo17 found that resistance is highly heritable and controlled by mostly additive gene action at three or four loci. In this study, we used 158 recombinant inbred (RI) lines derived from the cross B73 × Mo17 to map quantitative trait loci (QTL) governing resistance. The RI lines along with the parent inbred lines and the F1 were evaluated for PLS resistance in replicated trials over two winter growing seasons in southern Florida. Using the composite interval mapping (CIM) function of PLABQTL software, five QTL on four different chromosomes were found to control PLS resistance in Mo17. In addition, the × additive interaction between two of these QTL was found to be significant. Our results are in close agreement with the previous study, where generation mean analysis was used to study the inheritance of resistance to PLS.

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ABSTRACT A random set of recombinant inbred (RI) lines (F2:7) derived from the cross of the inbred lines Mo17 (resistant) and B73 (susceptible) were evaluated for resistance to southern leaf blight (SLB) caused by Cochliobolus heterostrophus race O. The RI lines were genotyped at a total of 234 simple sequence repeat, restriction fragment length polymorphism, or isozyme loci. Field plots of the RI lines were inoculated artificially with an aggressive isolate of C. heterostrophus race O in each of two growing seasons in North Carolina. Lines were rated for percent SLB severity two (1996) or three (1995) times during the grain-filling period. Data also were converted to area under the disease progress curve (AUDPC) and analyzed using the composite interval mapping option of the PLABQTL program. When means of disease ratings over years were fitted to models, a total of 11 quantitative trait loci (QTLs) were found to condition resistance to SLB, depending upon which disease ratings were used in the analyses. When the AUDPC data were combined and analyzed over environments, seven QTLs, on chromosomes 1, 2, 3, 4, 7, and 10 were found to come from the resistant parent Mo17. An additional QTL for resistance on chromosome 1 came from the susceptible parent B73. The eight identified QTLs accounted for 46% of the phenotypic variation for resistance. QTL x environment interactions often were highly significant but, with one exception, were the result of differences in the magnitude of QTL effects between years and not due to changes in direction of effects. QTLs on the long arm of chromosome 1 and chromosomes 2 and 3 had the largest effects, were the most consistently detected, and accounted for most of the phenotypic variance. No significant additive x additive epistatic effects were detected. These data support earlier reports of the polygenic inheritance of resistance to SLB of maize.

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ABSTRACT Randomly amplified polymorphic DNA (RAPD) markers and mating type were used to examine regional population structure of Setosphaeria turcica in the eastern United States. Of 251 maize-infecting isolates studied, 155 multilocus haplotypes were identified using 21 RAPD markers. Twelve isolates of the most common haplotype were identified from seven states and represented 5.2% of the sample. Although variation in genetic diversity was greatest within states rather than between either regions or states within regions, multidimensional scaling based on average taxonomic distances among state samples showed a close association of samples from IL, OH, IN, IA, MN, MI/WI, and NC. Isolates from GA/SC, VA/TN, PA/NY, and FL were distant from this core group that included midwestern states and NC and were distinct from one another. The high genotypic diversity, near equal mating type frequencies, and gametic phase equilibrium in samples from several states are inconsistent with a strictly clonal population. The population genetic structure of S. turcica is likely the result of both asexual and sexual reproduction. It is not clear whether sexual recombination actually occurs in the eastern United States or occurs elsewhere in tropical America and recombinant genotypes migrate to North America.

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ABSTRACT Fusarium ear rot and fumonisin contamination are serious problems for maize growers, particularly in the southeastern United States. The lack of maize genotypes highly resistant to infection by Fusarium verticillioides or to fumonisin contamination emphasizes the need for management strategies to prevent contamination by this mycotoxin. Information on the initial appearance of infection and fumonisin contamination of kernels and their increase over time is needed to determine if early harvest may be an appropriate control strategy. Maize ears from replicated studies at two locations in eastern North Carolina were harvested weekly, starting 2 weeks after pollination and continuing for 14 weeks. The percentage of kernels infected with F. verticillioides and the fumonisin contamination in the harvested samples were determined. Kernel infection by F. verticillioides and fumonisin contamination appeared as kernels neared physiological maturity and increased up to the average harvest date for maize in North Carolina. Beyond this date, the concentrations of fumonisin fluctuated. Under years conducive for fumonisin contamination, early harvest (greater than 25% grain moisture) may help reduce the level of contamination.

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AIMS: To describe the long term mortality experience of a cohort of 2187 male chemical production workers previously exposed to substantial levels of dioxin. METHODS: Vital status for a previously identified cohort was determined for an additional 10 years, to 1995. Dioxin exposures took place before 1983 and were sufficient to result in chloracne in 245 individuals. Mortality rates were compared with national figures and with a large pool of co-workers in unrelated production jobs. RESULTS: All cancers combined (standardised mortality ratio (SMR) = 1.0, 95% CI 0.8 to 1.1) and lung cancer (SMR = 0.8, 95% CI 0.6 to 1.1) were at or below expected levels. Rates for soft tissue sarcoma (SMR = 2.4, 95% CI 0.3 to 8.6) and non-Hodgkin's lymphoma (SMR = 1.4, 95% CI 0.6 to 2.7) were greater than expected overall, but below expectation in the update period. No trend of increasing risk with increasing exposure was observed for these cancers. Workers who developed chloracne had very low all-cancer rates (SMR = 0.5, 95% CI 0.3 to 1.0), and lung cancer rates (SMR = 0.3, 95% CI 0.0 to 1.1). CONCLUSIONS: We found no coherent evidence of increased cancer risk from dioxin exposure in this cohort. Our study highlights the wide range of cancer rates and the lack of consistency across dioxin studies.

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