Identification of selected hormonally active agents and animal mammary carcinogens in commercial and residential air and dust samples.

In order to characterize typical indoor exposures to chemicals of interest for research on breast cancer and other hormonally mediated health outcomes, methods were developed to analyze air and dust for target compounds that have been identified as animal mammary carcinogens or hormonally active agents and that are used in commercial or consumer products or building materials. These methods were applied to a small number of residential and commercial environments to begin to characterize the extent of exposure to these classes of compounds. Phenolic compounds, including nonylphenol, octylphenol, bisphenol A, and the methoxychlor metabolite 2,2-bis(p-hydroxyphenyl)-1,1,1-trichloroethane (HPTE), were extracted, derivatized, and analyzed by gas chromatography/mass spectrometry (GC/MS)-selective ion monitoring (SIM). Selected phthalates, pesticides, polycyclic aromatic hydrocarbons (PAHs), and polychlorinated biphenyls (PCBs) were extracted and analyzed by GC/MS-SIM. Residential and workplace samples showed detectable levels of twelve pesticides in dust and seven in air samples. Phthalates were abundant in dust (0.3-524 micrograms/g) and air (0.005-2.8 micrograms/m3). Nonylphenol and its mono- and di-ethoxylates were prevalent in dust (0.82-14 micrograms/g) along with estrogenic phenols such as bisphenol A and o-phenyl phenol. In this 7-sample pilot study, 33 of 86 target compounds were detected in dust, and 24 of 57 target compounds were detected in air. In a single sample from one home, 27 of the target compounds were detected in dust and 15 in air, providing an indication of chemical mixtures to which humans are typically exposed.

Effect of household preparation on levels of pesticide residues in produce.

In 1993, the National Academy of Sciences released a report on the effects of pesticides in the diets of infants and children, indicating that current tolerances do not take into account the eating habits and metabolism of young children. In response to that report, a study was undertaken to determine pesticide residues in raw agricultural commodities at levels below the tolerances established by the Environmental Protection Agency. The objective of the study was to determine whether normal household washing, peeling, and cooking procedures had any effect on pesticide residue levels. Low levels of pesticide residues were detected in 97 (40%) of the 243 samples analyzed. The number of samples containing detectable residues dropped to 47 (19%) after household preparation. Results indicate that residue levels in most commodities are substantially reduced after household preparation.

High-performance liquid chromatography/continuous-flow liquid secondary ion mass spectrometry of flavonoid glycosides in leguminous plant extracts.

A method for the identification of flavonoid glycosides utilizing continuous-flow liquid secondary ion mass spectrometry (CF-LSIMS) is presented. Minimum detectable quantities (MDQs) were determined for three model flavonoid glycosides (rutin, naringin and esculin) by both positive ion direct insertion probe (DIP)-LSIMS (1.6 nmol, 1.7 nmol and 730 pmol, respectively) and positive ion CF-LSIMS (330 pmol, 340 pmol and 290 pmol, respectively). Optimization of CF-LSIMS instrumental parameters was performed using the model compound rutin. Parameters optimized included mobile phase composition, glycerol concentration, mobile phase flow rate, ion source temperature, acceleration lens potential (amplitude and polarity) and Cs+ primary ion energy. Final instrumental optimization yielded an MDQ of 1.0 ng (1.6 pmol) for rutin by flow-injection CF-LSIMS. The optimization parameters were utilized in the identification of flavonoid glucosides in alfalfa (Medicago sativa L) and chickpea (Cicer arietinum) extracts by high-performance liquid chromatogrphy/CF-LSIMS. The results support the controversial identification of a major extract component as formononetin-7-O-glucoside-6"-malonate as opposed to afrormosin-7-O-glucoside-6"-malonate.

Handwipe sampling and analysis procedure for the measurement of dermal contact with pesticides.

A handwipe sampling and analysis procedure was developed for the measurement of dermal contact to pesticides. This procedure utilizes cellulose dressing sponges wetted with 2-propanol. A two-step wiping procedure is described that ensures that the entire hand is sampled. Removal efficiency experiments show that dry residues of the pesticides chlorpyrifos and pyrethrin I are quantitatively removed from hands immediately following contact. Results suggest that the procedure may remove pesticide residues that are deeply embedded in the skin and not removed by soap-and-water washing. Extraction efficiency studies for 29 other pesticides show that the proposed extraction method may be applicable for a wide range of pesticides including phenoxy-acid herbicides. Field testing of the procedure indicates that it is easily implemented by sampling personnel and readily accepted by children.

Synthesis of potential metabolites of ethyl (E)-4-[2-(3,4-dihydro-4,4-dimethyl-2H-1-benzopyran-6-yl)-1-propenyl] benzoate.

Potential metabolites of ethyl (E)-4-[2-(3,4-dihydro-4,4-dimethyl-2H-1-benzopyran-6-yl)-1-propenyl] benzoate were synthesized. The new compounds include ethyl 3-[3,4-dihydro-4,4-dimethyl-2H-1-benzopyran-6-yl]crotonate, 3-[3,4-dihydro-4,4-dimethyl-1H-1-benzopyran-6-yl]crotonic acid, 3,4-dihydro-4,4-dimethyl-2H-1-benzopyran-6-carboxylic acid, 4-[3,4-dihydro-4,4-dimethyl-2H-1-benzopyran-6-yl]delta 2-butenolide, ethyl (E)-4-[3,4-dihydro-4,4-dimethyl-2H-1-benzopyran-6-yl)-3-hydroxy-1- propenyl]benzoate, ethyl (E)-4-[2-(3,4-dihydro-4,4-dimethyl-2H-1-benzopyran-6-yl)-2-propenal] benzoate, and ethyl (E)-4-[2-(3,4-dihydro-4,4-dimethyl-2H-1-benzopyran-6-yl)-2-propenoic+ ++ acid]benzoate. Stereospecific oxidizing reagents and/or conditions were developed for these sensitive systems and include the use of SeO2, Clorox bleach, activated MnO2, and NaClO2 in the presence of resorcinol as a chlorine scavenger.

Citrate is a major component of snake venoms.

Citrate has been identified as a major component of snake venoms by gas liquid chromatography and mass spectrometry. The venoms of Bothrops asper, Crotalus atrox, Crotalus viridis viridis, Crotalus adamanteus, Sistrurus miliarius barbouri, Crotalus horridus horridus, Agkistrodon contortrix mokasen, Agkistrodon contortrix contortrix and Agkistrodon piscivorus piscivorus contain citrate at concentration levels which can serve as effective buffers. Calcium, magnesium, zinc, iron, sodium and potassium salts of citrate would be constituents of venom.

Stress Responses in Alfalfa (Medicago sativa L.) : V. Constitutive and Elicitor-Induced Accumulation of Isoflavonoid Conjugates in Cell Suspension Cultures.

The isoflavonoid conjugates medicarpin-3-O-glucoside-6''-O-malonate (MGM), afrormosin-7-O-glucoside (AG), and afrormosin-7-O-glucoside-6''-O-malonate (AGM) were isolated and characterized from cell suspension cultures of alfalfa (Medicago sativa L.), where they were the major constitutive secondary metabolites. They were also found in alfalfa roots but not in other parts of the plant. The phytoalexin medicarpin accumulated rapidly in suspension cultured cells treated with elicitor from Colletotrichum lindemuthianum, and this was subsequently accompanied by an increase in the levels of MGM. In contrast, net accumulation of afrormosin conjugates was not affected by elicitor treatment. Labeling studies with [(14)C]phenylalanine indicated that afrormosin conjugates were the major de novo synthesized isoflavonoid products in unelicited cells. During elicitation, [(14)C]phenylalanine was incorporated predominantly into medicarpin, although a significant proportion of the newly synthesized medicarpin was also conjugated. Treatment of (14)C-labeled, elicited cells with l-alpha-aminooxy-beta-phenylpropionic acid, a potent inhibitor of PAL activity in vivo, resulted in the initial appearance of labeled medicarpin of very low specific activity, suggesting that the phytoalexin could be released from a preformed conjugate under these conditions. Our data draw attention to the involvement of isoflavone hydroxylases during the constitutive and elicitor-induced accumulation of isoflavonoids and their conjugates in alfalfa cell cultures.