Cadmium in smoke particulates of regular and filter cigarettes containing low and high cadmium concentrations

Characterization of Fetal Thyroid Levels at Delivery among Appalachian Infants

Thyroid disorders are a frequently encountered issue during pregnancy and a cause of maternal and fetal morbidity. In regions like Appalachia that are particularly susceptible to health disparities, descriptive studies are needed to assist in identifying pathologic derangements. We sought to characterize fetal thyroid hormone levels at delivery and investigate whether or not maternal demographic characteristics affect the prevalence of neonatal thyroid disease. A cross-sectional analysis was conducted on 130 pregnant women recruited from the Tri-State region, incorporating areas of Kentucky, Ohio, and West Virginia. Total triiodothyronine (T3) (p = 0.4799), free T3 (p = 0.6323), T3 uptake (p = 0.0926), total thyroxine (T4) (p = 0.8316), free T4 (p = 0.0566), and Thyroid stimulating hormone (TSH) (p = 0.8745) levels were comparable between urban and rural newborns. We found no effect of hypertension status or nicotine levels on fetal umbilical cord thyroid hormone levels. Maternal diabetic status was associated with lower T4 (p = 0.0099) and free T4 (p = 0.0025) levels. Cotinine affected levels of T4 (p = 0.0339). In regard to maternal Body Mass Index (BMI), there was an increase in total T3 as BMI increased (p = 0.0367) and no significant difference in free T3, T3 uptake, T4, free T4, or TSH. There was a negative correlation between TSH and 1 min Apgar scores (p = 0.0058). Lead and cadmium have been implicated to alter TSH levels, but no correlation was found in our study (r² = 0.0277). There were no differences in cord blood between urban (37.3 ± 10.3 fmol/ug DNA) and rural (70.5 ± 26.8 fmol/ug DNA) benzo(a)pyrene DNA adducts (p = 0.174). Thyroid disorders present a unique opportunity for the prevention of perinatal morbidity and mortality, since maternal treatment, as well as maternal demographic characteristics, can have direct fetal effects.

An international literature survey of "IARC Group I carcinogens" reported in mainstream cigarette smoke

The International Agency for Research on Cancer (IARC) currently lists 44 individual chemical agents, 12 groups or mixtures of chemicals and 13 exposure circumstances as "Group 1 human carcinogens". A comprehensive search of the published literature revealed that nine of the 44 chemical agents classified as "Group I carcinogens" by IARC have been reported to occur in mainstream cigarette smoke. The other 35 have never been reported to occur in cigarette smoke. The nine agents reported are benzene, cadmium, arsenic, nickel, chromium, 2-naphthyl-amine, vinyl chloride, 4-aminobiphenyl and beryllium. The reported yields of each of these nine agents in mainstream smoke varies widely. The range of yields reported for a given compound is influenced by the type of cigarette tested and when the analysis was conducted. In micrograms/cigarette, the ranges that have been reported for each of the nine compounds are: benzene (0.05-104), cadmium (0-6.67), arsenic (0-1.4), nickel (0-0.51), chromium (0.0002-0.5), 2-naphthylamine (0.0002-0.022), vinyl chloride (0.0013-0.0158), 4-aminobiphenyl (0.00019-0.005) and beryllium (0-0.0005). Although some of the variation in reported yields may be due to differences in analytical methodology, several correlations between the yield of a particular chemical in mainstream smoke and certain cigarette characteristics were observed. For example, charcoal filtration was associated with reduced vinyl chloride, and the concentration of sodium nitrate in the tobacco was positively correlated with the mainstream yield of both 2-naphthylamine and 4-aminobiphenyl. Benzene yield in mainstream cigarette smoke was correlated with the amount of tobacco burned and with the 'tar' level. Agronomic factors such as production practices and soil characteristics, and environmental conditions such as rainfall, reportedly influence the accumulation of metals, for example, cadmium, beryllium, chromium, nickel and arsenic, in the leaf. The use of fertilizers low in nitrate and heavy metals would be expected to substantially reduce the yields of most of the "IARC Group 1 carcinogens" reported to occur in mainstream cigarette smoke. Additionally, modifications in cigarette design, for instance, the use of enhanced charcoal filters or heated instead of burned tobacco, would also be expected to reduce the yields of several of these agents.

In vivo cadmium treatment alters natural killer activity and large granular lymphocyte number in the rat

The effects of oral exposure for nearly 6 months to Cd (200 or 400 ppm) on rat natural killer (NK) activity were investigated. No significant differences in body and thymus weights were observed. Peripheral blood lymphocyte (PBL) number was consistently higher in treated rats throughout the treatment; the number of spleen cells decreased during the first 50 days, and then reached a level higher than in controls. NK activity, evaluated in a 4-h chromium release assay against YAC-1 target cells, was altered in treated rats: lower up to day 30, and then higher. In parallel, a reduction of the large granular lymphocytes (LGL) was found initially in the peripheral blood of Cd-treated rats, followed by a persistent marked increase. These changes were closely correlated with the altered distribution of CD8+ aGM1+ CD5- cells, which mostly consist of NK cells. Fluorescence-activated cell sorter (FACS) analysis revealed a decrease of cell subset with a typical NK phenotype during the first 30 days of treatment and a clear increase thereafter. Post-exposure observations indicated that all these effects disappeared with a return to control values 2 months after cessation of treatment. These findings suggest that in vivo administration of Cd induces both inhibitory and stimulatory effects on rat NK cell number and cytotoxic activity, depending on time of exposure.