Instruct: Given a question, retrieve relevant passages that answer the question.
Query: Exponent Inc.
Context: In 1954 the tobacco industry paid to publish the “Frank Statement to Cigarette Smokers” in hundreds of U.S. newspapers. It stated that the public's health was the industry's concern above all others and promised a variety of good-faith changes. What followed were decades of deceit and actions that cost millions of lives. In the hope that the food history will be written differently, this article both highlights important lessons that can be learned from the tobacco experience and recommends actions for the food industry. Methods: A review and analysis of empirical and historical evidence pertaining to tobacco and food industry practices, messages, and strategies to influence public opinion, legislation and regulation, litigation, and the conduct of science. Findings: The tobacco industry had a playbook, a script, that emphasized personal responsibility, paying scientists who delivered research that instilled doubt, criticizing the “junk” science that found harms associated with smoking, making self-regulatory pledges, lobbying with massive resources to stifle government action, introducing “safer” products, and simultaneously manipulating and denying both the addictive nature of their products and their marketing to children. The script of the food industry is both similar to and different from the tobacco industry script. Conclusions: Food is obviously different from tobacco, and the food industry differs from tobacco companies in important ways, but there also are significant similarities in the actions that these industries have taken in response to concern that their products cause harm. Because obesity is now a major global problem, the world cannot afford a repeat of the tobacco history, in which industry talks about the moral high ground but does not occupy it.
BACKGROUND: Capsinoids-nonpungent capsaicin analogs-are known to activate brown adipose tissue (BAT) thermogenesis and whole-body energy expenditure (EE) in small rodents. BAT activity can be assessed by [¹⁸F]fluorodeoxyglucose-positron emission tomography (FDG-PET) in humans. OBJECTIVES: The aims of the current study were to examine the acute effects of capsinoid ingestion on EE and to analyze its relation to BAT activity in humans. DESIGN: Eighteen healthy men aged 20-32 y underwent FDG-PET after 2 h of cold exposure (19°C) while wearing light clothing. Whole-body EE and skin temperature, after oral ingestion of capsinoids (9 mg), were measured for 2 h under warm conditions (27°C) in a single-blind, randomized, placebo-controlled, crossover design. RESULTS: When exposed to cold, 10 subjects showed marked FDG uptake into adipose tissue of the supraclavicular and paraspinal regions (BAT-positive group), whereas the remaining 8 subjects (BAT-negative group) showed no detectable uptake. Under warm conditions (27°C), the mean (±SEM) resting EE was 6114 ± 226 kJ/d in the BAT-positive group and 6307 ± 156 kJ/d in the BAT-negative group (NS). EE increased by 15.2 ± 2.6 kJ/h in 1 h in the BAT-positive group and by 1.7 ± 3.8 kJ/h in the BAT-negative group after oral ingestion of capsinoids (P < 0.01). Placebo ingestion produced no significant change in either group. Neither capsinoids nor placebo changed the skin temperature in various regions, including regions close to BAT deposits. CONCLUSION: Capsinoid ingestion increases EE through the activation of BAT in humans. This trial was registered at http://www.umin.ac.jp/ctr/ as UMIN 000006073.
BACKGROUND: Extraintestinal Escherichia coli infections are associated with specialized extraintestinal pathogenic E. coli (ExPEC) strains and, increasingly, with antimicrobial resistance. The food supply may disseminate ExPEC and antimicrobial-resistant E. coli. METHODS: In a prospective survey of 1648 diverse food items from 10 retail markets in the Minneapolis-St. Paul area during 2001-2003, selective cultures and disk-diffusion assays for the isolation and characterization of antimicrobial-resistant E. coli and polymerase chain reaction-based assays and O serotyping to define ExPEC-associated traits were performed. RESULTS: E. coli contamination exhibited a prevalence gradient from miscellaneous foods (9%), through beef or pork (69%), to poultry (92%; P<.001). Among E. coli-positive samples, similar prevalence gradients were detected for antimicrobial resistance (27%, 85%, and 94% of samples, respectively; P<.001) and ExPEC contamination (4%, 19%, and 46%, respectively; P<.001). By multivariate analysis, beef or pork and poultry from natural-food stores exhibited reduced risks of E. coli contamination and antimicrobial resistance. Indirect evidence suggested on-farm selection of resistance. Four food-source ExPEC isolates (from pea pods, turkey parts, ground pork, and vegetable dip) closely resembled selected human clinical isolates by O antigen and genomic profile. CONCLUSIONS: Retail foods may be an important vehicle for community-wide dissemination of antimicrobial-resistant E. coli and ExPEC, which may represent a newly recognized group of medically significant foodborne pathogens.
Over the last 40 years there have been constant reports concerning environmental chemicals with hormone-like effects in wildlife. An endocrine disruptor is an exogenous substance that causes adverse health effects in an intact organism or its progeny, secondary to changes in endocrine function. Endocrine disruptors of widely diverse chemical structures that have oestrogenic properties are known as oestrogenic xenobiotics or xenoestrogens. Some of these substances, such as phytoestrogens and mycoestrogens, can come from diet or from the environment. Although the oestrogenic activity of these substances is weaker than that of oestradiol, new chemicals with endocrine disrupting potential continue to be discovered, inadvertent forms of exposure are constantly being identified, and there is increasing concern about cumulative effects. Studies in the 1960s and 1970s characterized the oestrogenicity of a number of industrial compounds and the pesticides o,p-DDT, kepone, methoxychlor, phenolic derivatives and polychlorinated biphenyls (PCBs). In the last 5 years, several environmental chemicals have been added to the list of xenoestrogens, including the pesticides toxaphene, dieldrin and endosulphan, and several different compounds used in the food industry, antioxidants such a t-butylhydroxyanisole; plasticizers such as benzylbutylphthalate and 4-OH-alkylphenols; and substances used in dental restorations, such as bisphenol-A. The relevance of these newly discovered endocrine disruptors to human health is now starting to emerge. The few studies that have investigated their effect in humans point in the same direction: if there is indeed an association between exposure to substances with hormone-disruptive activity and certain disorders of endocrine organs, the incidence of such disorders would be greater in areas where exposure to agents with this activity is high. A closer scrutiny is required to determine whether these newly discovered endocrine disrupting chemicals contribute, together with oestrogenic pesticides, to the exposure of humans to xenoestrogens.
Eosinophilia–myalgia syndrome (EMS) is characterized by subacute onset of myalgias and peripheral eosinophilia, followed by chronic neuropathy and skin induration. An epidemic of EMS in 1989 was linked to L-tryptophan consumption originating from a single source. Following the Food and Drug Administration (FDA) ban on the sale of L-tryptophan, the incidence of EMS declined rapidly. Moreover, no new cases have been published since the FDA ban was lifted in 2005. We report the clinical, histopathological and immunogenetic features of a new case of L-tryptophan-associated EMS along with evidence of activated transforming growth factor-ß and interleukin-4 signaling in the lesional skin.
Dietary microparticles are non-biological bacterial-sized particles of the gastrointestinal lumen that occur due to endogenous formation (calcium phosphate) or following oral exposure (exogenous microparticle). In the UK, about 40 mg (1012) of exogenous microparticles are ingested per person per day, through exposure to food additives, pharmaceutical/supplement excipients or toothpaste constituents. Once ingested, exogenous microparticles are unlikely to pass through the gastrointestinal tract without adsorbing to their surfaces some ions and molecules of the intestinal lumen. Both entropy and ionic attraction drive such interactions. Calcium ions are especially well adsorbed by dietary microparticles which then provide a positively charged surface for the attraction (adsorption) of other organic molecules such as lipopolysaccharides, peptidoglycans or protein antigen from the diet or commensal flora. The major (but not only) sites of microparticle entry into intestinal tissue are the M-cell rich lymphoid aggregates (termed Peyer’s patches in the small bowel). Indeed, it is well established that this is an efficient transport route for non-biological microparticles although it is unclear why. We hypothesise that this pathway exists for “endogenous microparticles” of calcium phosphate, with immunological and physiological benefit, and that “exogenous dietary microparticles”, such as titanium dioxide and the silicates, hijack this route. This overview focuses on what is known of these microparticles and outlines their potential role in immune tolerance of the gut (endogenous microparticles) or immune activation (exogenous microparticles) and inflammation of the gut.
Enterobacterial strains producing clavulanic-acid-inhibited extended-spectrum β-lactamases (ESBLs) are increasingly reported worldwide. Conventional detection of ESBL production remains time-consuming (24 to 48 h). Therefore, the ESBL NDP (Nordmann/Dortet/Poirel) test was developed for a rapid identification of ESBLs in Enterobacteriaceae. This biochemical test was based on the in vitro detection of a cephalosporin (cefotaxime) hydrolysis that is inhibited by tazobactam addition. The ESBL activity was evidenced by a color change (red to yellow) of a pH indicator (red phenol) due to carboxyl-acid formation resulting from cefotaxime hydrolysis that was reversed by addition of tazobactam (positive test). The ESBL NDP test was applied to cultured strains (215 ESBL producers and 40 ESBL nonproducers). Its sensitivity and specificity were 92.6% and 100%, respectively. Its sensitivity (100%) was excellent for detection of CTX-M producers. A few ESBL producers (n = 16) that remained susceptible to cefotaxime were not detected. The test was also evaluated on spiked blood cultures and showed excellent sensitivity and specificity (100% for both). The test was rapid (less than 1 h) and cost-effective. It can be implemented in any health care facility and is well adapted for infection control purposes in particular.
In this study, solid fermentation of steamed black soybean with various GRAS (Generally recognized as safe) filamentious-fungi including Aspergillus awamori, Aspergillus oryzae BCRC 30222, Aspergillus sojae BCRC 30103, Rhizopus azygosporus BCRC 31158 and Rhizopus sp. No. 2 was performed. Mutagenicity and antimutagenicity of the methanol extracts of unfermented and fermented steamed black soybeans against 4-nitroquinoline-N-oxide (4-NQO), a direct mutagen and Benzo[a]pyrene (B[a]P), an indirect mutagen, on Salmonella Typhimurium TA100 and TA 98, were examined. The methanol extracts of unfermented and fermented steamed black soybeans show no mutagenic activity for either test strains at the doses tested. The extracts inhibited mutagenesis by either 4-NQO or B[a]P in S. Typhimurium TA100 and TA98. Fermentation with fungi also enhanced the antimutagenic effect of black soybean while the antimutagenic effect of the fermented black soybeans extract varied with the starter organism, mutagen, and test strain of S. Typhimurium examined. Generally, the extracts of A. awamori-fermented black soybean exhibited the highest antimutagenic effect. With strain TA100, the inhibitory effects of 5.0 mg of A. awamori-fermented black soybean extract per plate on the mutagenic effects of 4-NQO and B[a]P were 92% and 89%, respectively, while the corresponding rates for extract of unfermented were 41% and 63%, respectively. With strain 98, the inhibition rates were 94 and 81% for the fermented bean extract and 58% and 44% for the unfermented bean extracts. Testing of extracts prepared from black soybean by A. awamori at temperatures 25, 30 and 35 degrees C and for times of 1-5 days revealed that, generally, the extract prepared from beans fermented at 30 degrees C for 3 days exhibited the greatest inhibition against the mutagenic effects of 4-NQO and B[a]P.
Pollutant chemicals that are widespread in the environment can affect endocrine signaling, as evidenced in laboratory experiments and in wildlife with relatively high exposures. Although humans are commonly exposed to such pollutant chemicals, the exposures are generally low, and clear effects on endocrine function from such exposures have been difficult to demonstrate. Several instances in which there are data from humans on exposure to the chemical agent and the endocrine outcome are reviewed, including age at weaning, age at puberty, and sex ratio at birth, and the strength of the evidence is discussed. Although endocrine disruption in humans by pollutant chemicals remains largely undemonstrated, the underlying science is sound and the potential for such effects is real.
A streptomycete was isolated from an Easter Island soil sample and found to inhibit Candida albicans, Microsporum gypseum and Trichophyton granulosum. The antibiotic-producing microorganism was characterized and identified as Streptomyces hygroscopicus. The antifungal principle was extracted with organic solvent from the mycelium, isolated in crystalline form and named rapamycin. Rapamycin is mainly active against Candida albicans; minimum inhibitory concentration against ten strains ranged from 0.02 to 0.2 mug/ml. Its apparent activity against Microsporum gypseum and Trichophyton granulosum is lower because of its instability in culture media on prolonged incubation required by these fungi. No activity was observed against gram-positive and gram-negative bacteria. Acute toxicity in mice is low.
Respiratory exposure to diacetyl and diacetyl-containing flavorings used in butter-flavored microwave popcorn (BFMP) causes lung disease, including bronchiolitis obliterans (BO), in flavorings and popcorn manufacturing workers. However, there are no published reports of lung disease among BFMP consumers. We present a case series of three BFMP consumers with biopsy-confirmed BO. We review data relating to consumer exposures, estimate case exposures, and compare them to diacetyl-containing flavoring-exposed manufacturing workers with lung disease. These consumer cases' exposure levels are comparable to those that caused disease in workers. We were unable to identify any other exposures or diseases known or suspected to cause BO in these cases. BFMP poses a significant respiratory risk to consumers. Some manufacturers have substituted diacetyl with other alpha-diketones that are likely to pose a similar risk. Simple consumer practices such as cooling the popcorn bag would eliminate the risk of severe lung disease.
Human gammadeltaT lymphocytes are a subset of T cells and are a first line of defense against microbes and tumors. These gammadeltaT cells can be primed by nitrogen-containing bisphosphonates, and certain short-chain alkylamines. These primed gammadeltaT cells have an enhanced capacity to proliferate and to secrete cytokines upon ex vivo exposure to a wide variety of microbes and tumor cells. The largest dietary source of alkylamines is L-theanine, an amino acid unique to tea beverages that is catabolized to ethylamine. Supplementation of subjects with capsules containing L-theanine and catechins has recently been shown to decrease the incidence of cold and flu symptoms, while enhancing gammadeltaT cell function.
The anti-genotoxic effect of Ocimum sanctum L. extract was studied against the genotoxic effect induced by a synthetic progestin cyproterone acetate, on human lymphocytes using chromosomal aberrations, mitotic index, sister chromatid exchanges and replication index as a parameters. About 30 microM of cyproterone acetate was treated with O. sanctum L. infusion, at dosages of 1.075 x 10(-4), 2.125 x 10(-4) and 3.15 x 10(-4) g/ml of culture medium. A clear dose-dependent decrease in the genotoxic damage of cyproterone acetate was observed, suggesting a possible modulating role of the plant infusion. The results of the present study suggest that the plant infusion per se does not have genotoxic potential, but can modulate the genotoxicity of cyproterone acetate on human lymphocytes in vitro.
AV119 is a patented blend of two sugars from avocado that can induce human beta-defensin-2 production by normal human keratinocytes. In this study, we analysed the effect of AV119 on growth and invasiveness of Malassezia furfur, a dimorphic, lipid-dependent yeast that is part of the normal human cutaneous commensal flora. The ability to modulate the expression of the proinflammatory and immunomodulatory cytokines in normal human keratinocytes was also investigated. Microbiological assay demonstrated that this sugar induced the aggregation of yeast cells and inhibited the invasiveness of M. furfur, without affecting its growth. Real-time PCR analysis demonstrated that AV119 was able to modulate the HBD-2 response in treated keratinocytes, reaching a maximum after 48-h treatment, and to induce the recovery of a satisfactory proinflammatory response in human keratinocytes. As AV119 can induce aggregation of yeast cells, thus inhibiting their penetration into the keratinocytes, the sugar could be used in the preparation of cosmetics or pharmacological drugs to inhibit colonization of the skin by pathogenic strains of M. furfur.
The regular occurrence of a peak due to an unidentified substance (X) in the gas chromatographic traces obtained from phenolic extracts of urine from human pregnant and non-pregnant females has been reported. The biphasic excretion of X with maxima in the luteal phase of the ovulatory cycle and relatively high levels in the first trimester of pregnancy were noteworthy and suggested that the substance may have a biological significance. Close similarities between the excretory pattern, the chemical and chromatographic properties of X and of those of the known phenolic steroids suggested initially that this compound was steroidal in nature. The same, or a similar, substance seems to be excreted in the vervet monkey (Cercopithecus aethiops pygerythrus). We now report the excretory pattern of X in more detail, the isolation of the pure compound from pooled pregnancy urine and the chemical structure. The structure determined by mass spectrometry, IR spectroscopy and NMR spectrometry is: trans-(+/-)-3,4-bis[(3-hydroxyphenyl)methyl]dihydro-2-(3H)-furanone (HPMF) and was confirmed by synthesis.
A human breast cancer cell line (MCF-7) was used to develop an in vitro screening assay for the detection of xenoestrogenic environmental pollutants. MCF-7 cells were cultured in DMEM containing 5% fetal bovine serum (FBS). An estrogenic response was defined as an increase in the frequency of proliferating MCF-7 cells, and was measured using a thymidine analog, bromodeoxyuridine, and flow cytometry. Di-2-ethylhexyl phthalate (DEHP) and 4-n-nonylphenol (4-n-NP) were used as model chemicals. The proliferation rate of S-phase cells after 24 h of exposure to various concentrations of 17beta-estradiol and to model compounds was compared with a positive and a negative control, containing 1 nM 17beta-estradiol and 0.1% ethanol, respectively. DEHP and 4-n-NP increased the frequency of proliferating MCF-7 cells in a dose-dependent manner. The lowest concentration that significantly increased the proliferation of MCF-7 cells was 10 microM for DEHP and 1 microM for 4-n-NP. The results showed that the assay is accurate and quick to perform. It may prove a valuable tool for screening potential estrogen-mimicking environmental pollutants.
PURPOSE OF REVIEW: Capsaicin and its nonpungent analog (capsinoids) are known to be food ingredients that increase energy expenditure and decrease body fat. This article reviews the role of brown adipose tissue (BAT) for the thermogenic effect of these compounds in humans and proposes the possibility of some other antiobesity food ingredients. RECENT FINDINGS: A single oral ingestion of capsinoids increases energy expenditure in human individuals with metabolically active BAT, but not those without it, indicating that capsinoids activate BAT and thereby increase energy expenditure. This finding gave a rational explanation for discrepant results of the effects of capsinoids in the previous studies. Human BAT may be largely composed of inducible 'beige' adipocytes more than typical brown adipocytes because its gene expression patterns are similar to beige cells isolated from murine white fat depots. In fact, preadipocytes isolated from supraclavicular fat deposits - where BAT is often detected - are capable of differentiating into brown-like adipocytes in vitro, providing evidence of inducible brown adipogenesis in adult humans. SUMMARY: As human BAT may be inducible, a prolonged ingestion of capsinoids would recruit active BAT and thereby increase energy expenditure and decrease body fat. In addition to capsinoids, there are numerous food ingredients that are expected to activate BAT and so be useful for the prevention of obesity in daily life.
The aim of this study was to determine the capability of Melissa officinalis L. (Lemon balm) infusion on improvement of oxidative stress status in radiology staff that were exposed to persistent low-dose radiation during work. The study was a before-after clinical trial performed on 55 radiology staff. They were asked to drink Lemon balm infusion which was prepared like a tea bag twice daily (1.5 g/100 mL) for 30 days. In the plasma, lipid peroxidation, DNA damage, catalase, superoxide dismutase, myeloperoxidase, and glutathione peroxidase activity were measured before and after using Lemon balm infusion.Use of Lemon balm infusion in radiology unit workers resulted in a significant improvement in plasma levels of catalase, superoxide dismutase, and glutathione peroxidase and a marked reduction in plasma DNA damage, myeloperoxidase, and lipid peroxidation. It is concluded that infusion of Lemon balm markedly improve oxidative stress condition and DNA damage in radiology staff when used as a dietary supplement for radiation protection.
Two populations of immigrants to London and to the West Indies from the Indian subcontinent have higher than expected morbidity and mortality from atherosclerosis but do not show the commonly accepted major risk factors. This study investigated the hypothesis that ghee, a clarified butter product prized in Indian cooking, contains cholesterol oxides and could therefore be an important source of dietary exposure to cholesterol oxides and an explanation for the high atherosclerosis risk. Substantial amounts of cholesterol oxides were found in ghee (12.3% of sterols), but not in fresh butter, by thin-layer and high-performance-liquid chromatography. Dietary exposure to cholesterol oxides from ghee may offer a logical explanation for the high frequency of atherosclerotic complications in these Indian populations.
Alkylphenols are widely used as plastic additives and surfactants. We report the identification of an alkylphenol, nonylphenol, as an estrogenic substance released from plastic centrifuge tubes. This compound was extracted with methanol, purified by flash chromatography and reverse-phase high performance liquid chromatography, and identified by gas chromatography-mass spectrometry. Nonylphenol induced both cell proliferation and progesterone receptor in human estrogen-sensitive MCF7 breast tumor cells. Nonylphenol also triggered mitotic activity in rat endometrium; this result confirms the reliability of the MCF7 cell proliferation bioassay. The estrogenic properties of alkylphenols, specifically nonylphenols, indicate that the use of plasticware containing these chemicals in experimental and diagnostic tests may lead to spurious results, and these compounds as well as alkylphenol polyethoxylates may also be potentially harmful to exposed humans and the environment at large.
Objectives To determine the cytotoxicity of three commercial mouthrinses Klorhex, Andorex and Tanflex on buccal epithelial cells using micronucleus (MN) test. Materials and Methods 28 patients with aged 16–24 undergone three mouthrinses’ application were analyzed before and after one week exposure. Physiologic saline was used for the control group. The MN incidence was scored in the buccal epithelial of each participants. The difference in pre- and post-treatment after one week incidence of MN and plaque (PI) and gingival indices (GI) was compared by non-parametric statistical tests. Results The micronuclei incidence increased in Klorhex, Tanflex and Andorex groups after exposure to mouth rinses (P<.05). But when compared with the control group, there was not any difference between Andorex and control group (P>.05). In the other study groups, MN incidence was significantly increased after 7 days treatment (P<.05). GI scores of all groups were decreased significantly (P<.05). PI scores were decreased only in the Klorhex group (P<.05). Conclusions Our primary findings support the presence of possible cytotoxic effects of the mouthrinses on gingival epithelial cells.
Brown adipose tissue (BAT) can be identified by (18)F-fluorodeoxyglucose (FDG)-positron emission tomography (PET) in adult humans. Thirteen healthy male volunteers aged 20-28 years underwent FDG-PET after 2-h cold exposure at 19 °C with light-clothing and intermittently putting their legs on an ice block. When exposed to cold, 6 out of the 13 subjects showed marked FDG uptake into adipose tissue of the supraclavicular and paraspinal regions (BAT-positive group), whereas the remaining seven showed no detectable uptake (BAT-negative group). The BMI and body fat content were similar in the two groups. Under warm conditions at 27 °C, the energy expenditure of the BAT-positive group estimated by indirect calorimetry was 1,446 ± 97 kcal/day, being comparable with that of the BAT-negative group (1,434 ± 246 kcal/day). After cold exposure, the energy expenditure increased markedly by 410 ± 293 (P < 0.05) and slightly by 42 ± 114 kcal/day (P = 0.37) in the BAT-positive and -negative groups, respectively. A positive correlation (P < 0.05) was found between the cold-induced rise in energy expenditure and the BAT activity quantified from FDG uptake. After cold exposure, the skin temperature in the supraclavicular region close to BAT deposits dropped by 0.14 °C in the BAT-positive group, whereas it dropped more markedly (P < 0.01) by 0.60 °C in the BAT-negative group. The skin temperature drop in other regions apart from BAT deposits was similar in the two groups. These results suggest that BAT is involved in cold-induced increases in whole-body energy expenditure, and, thereby, the control of body temperature and adiposity in adult humans.
Ergothioneine is a native membrane-impermeable thiol compound that is specifically accumulated in cells via the organic cation transporter OCTN1. In humans, OCTN1 and ergothioneine have been implicated in the etiopathogenesis of autoimmune disorders. However, available evidence about dietary sources and the functional role of ergothioneine in human physiology is scarce. Here, we analyzed the ergothioneine content in common foods using liquid chromatography tandem-mass spectrometry. Additionally, we assessed the protective potency of ergothioneine against various oxidative stressors in OCTN1-expressing cells in comparison with the main intracellular thiol antioxidant glutathione by evaluating cell viability with the MTT reduction assay. Only some food contained ergothioneine with highest concentrations detected in specialty mushrooms, kidney, liver, black and red beans, and oat bran. Ergothioneine exhibited cell protection only against copper(II)-induced toxicity but was far less potent than glutathione, indicting that ergothioneine is not involved in the intracellular antioxidant thiol defense system.
4-Methylimidazole (4MI) is used in the manufacture of pharmaceuticals, photographic chemicals, dyes and pigments, cleaning and agricultural chemicals, and rubber. It has been identified as a by-product of fermentation in foods and has been detected in mainstream and side stream tobacco smoke. 4MI was studied because of its high potential for human exposure. Groups of 50 male and 50 female F344/N rats were fed diets containing 0-, 625-, 1,250-, or 2,500-ppm 4MI (males) or 0-, 1,250-, 2,500-, or 5,000-ppm 4MI (females) for 106 weeks. Based on the food consumption the calculated average daily doses were approximately 30, 55, or 115 mg 4MI/kg body weight to males and 60, 120, or 250 mg 4MI/kg to females. Survival of all exposed groups of males and females was similar to that of the control groups. Mean body weights of males in the 1,250- and 2,500-ppm groups and females in the 2,500- and 5,000-ppm groups were less than those of the control groups throughout the study. Feed consumption by 5,000-ppm females was less than that by the controls. Clonic seizures, excitability, hyperactivity, and impaired gait were observed primarily in 2,500- and 5,000-ppm females. The incidence of mononuclear cell leukemia in the 5,000-ppm females was significantly greater than that in the controls. The incidences of hepatic histiocytosis, chronic inflammation, and focal fatty change were significantly increased in all exposed groups of male and female rats. The incidences of hepatocellular eosinophilic and mixed cell foci were significantly increased in 2,500-ppm males and 5,000-ppm females. Groups of 50 male and 50 female B6C3F1 mice were fed diets containing 0-, 312-, 625-, or 1,250-ppm 4MI for 106 weeks. Based on the food consumption the calculated average daily doses were approximately 40, 80, or 170 mg 4MI/kg body weight to males and females. Survival of all exposed groups of males and females was similar to that of the control groups. Mean body weights of males and females in the 1,250-ppm groups and that in the 312- and 625-ppm females were less than those of the control groups. Feed consumption by exposed groups of male and female mice was similar to that by the controls. The incidences of alveolar/bronchiolar adenoma in all exposed groups of females, alveolar/bronchiolar carcinoma in 1,250-ppm males, and alveolar/bronchiolar adenoma or carcinoma (combined) in 1,250-ppm males and 625- and 1,250-ppm females were significantly greater than those in the control groups. The incidence of alveolar epithelial hyperplasia was significantly increased in the 1,250-ppm females. 4MI is carcinogenic inducing alveolar/bronchiolar adenoma and carcinoma in male and female mice. 4MI may also induce mononuclear cell leukemia in female rats.
Laboratory and population-based studies suggest that exposure to environmental toxicants may be one of several triggers for the development of endometriosis. We discuss evidence that modulation of the endometrial endocrine-immune interface could mechanistically link toxicant exposure to the development of this disease. Capsule Summary: Environmental toxicant exposure induces an inflammatory-like endometrial response that may promote the development of endometriosis.