1.9.1 EnvironmenCal exposure
The most likely mode of exposure is ingestion of cooked food products containing IQ, such as broiled or fried beef, fish. or eggs (Radian, 1991). IQ also
is present in cigarette smoke (Y amashlta et al; 1986). Based upon analysis of
various foodstuffs ancf analysis of HCA content (including IQ), estimated daily
exposure of the U.S. popuJaLion 10 hetcrocyclic aroau1tic amines ranges from I 00
ng to I O g per day. It is difficult to quantify overall U.S. CJCposure. because IQ
content depends on the meat. cooking temperature, and manner of preparation
(Tu.resky et al. 1993). Individual IQ intake ,\-ould depe.nd upon these factors.
Table 2.3: Physical and chemical propcnies of IQ
Property Information Rcrc�ncc
Molecular weight 198.23 Budnvnri et al. ( 1996) Chcmfinder ( 1999)
Color light tan Chcmfindcr ( 1999),
Budnvari et al. (1996) PhysicaJ state crystalline solid Chem finder ( 1999),
Budavari et al. (1996) Melting point ("C) > 300 IARC (1993)
Solubility:
\Vater at 20 ° C insoluble CSL (1987)
Dimethylsulfoxide soluble lARC (1993)
95% Ethanol ot J 6 ° C I - 10 mg/mL Rlldian (1991)
Methanol soluble lARC (1993)
Acids (dilute) soluble CSL (1987)
Alcohols (dilute) soluble CSL (1987)
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2.9.2 Occupational exposure
Occupational exposure to IQ may occur where employees worJc with broiled or fried foods, such as beef, fish, or eggs. No studies were found that dealt with IQ intake among workers who prepared or served such foods. It is unlcnown whether exposure by
routes other than ingestion (i.e., dermal or inhalation) would occur in this setting.
IQ induced a significant dose-dependent increase in base--pair substitution mutations at the hu<J46 allele in S.. ryphimurlum strain TA I 00 in the presence of exogenous rut-liver S9 metabolic activation. The observed mutations ",:re predominantly GCT A rransversions ,vith apronounccd preference for the second codon position, CCCCAC. IQ \\'ilS, ho,vcver, not mutagcoic in S. l)phimurium strain TA153S
in the presence of rat-liver S9 metabolic activation. The dose used \\.---US 30-fold th:u needed to induce a three fold increase in reversion in S. l)phlmurium strain TAJOO (Koch rt of. 1998).
IQ induces mutations in S. l)phlmurlum. E. coll, and meristCJ:Mtie cdJs of soybca.n pl11nu. IQ l.nduccs muuiuons and DNA dllmage in D mrlanogastrr IIDd is both
clastogenic and mutagcnlc in nwnma.lio.n cells In ,•ltro and In ,·h.'O �fuuuioos in c-H 11
-ra.s and p53 genes IM:l'C foWld in some IQ-induced ZymblLI gland carcinomAS m nus.
Mamma.Jian c:clls rich In cytochrome P-450- I A2 and N..cctyltransf�2 vc more suscq,tible 10 IQ induction of muwions. SCEs. CA. and DNJ.\ brcaLs. thAo cells not exp.cssin g these proteins.
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2.10 Flavonoids in roods.
Over 4,000 types of flavonoids compounds have been identified in vascular
planis nnd these vary in type and quantity due to variations in plant growth , condition and maturity(Picpoint, 1986). Plants have evolved to produce Oavonoids to protect against fungal parasites (Harbomc, 1986, 1988), herbivores, pathogens and oxidative
ceU injury ( s,.,.11in, 1986). Flavonoids make almost always the vol um e and rcsponsble for the colour of flo.,.ters, fruits and sometimes leaves. e.g yelJov,s Onvonoid (chaleones, aurones), and red, blue, or purple anth ocy anins (Coultale,1990) . [n red
\vine, lllnnins arc formed by the poymcrisations of anthocynnins and other Oavonoids producing the \voe 's characteristic colors, ilo:vours and astringency( Swain , 1986).
Flavonoids arc also in the epidermal cells ,vbere they ensure protection apin.st the damaging effects of UV rodintion. All Flavoooids- approximateJy 4000 h4 Y e a common biosynthetie origin, thcrefon: possessing the same look in structural element Only a smAII no of plant species have been examined systemAtic:ally for their flavonoid content (H111bome, 1988) and therefore idcntifiauion llnd qu:l.lific:atJoo of GlJ
the t)'J>CS offlavonoid.s conswncd by humans is incomplete {Picpoint.1986).
FJavonolds arc a a:roup of polyphcnolie compound ",lb d1\erse chcmiaal structure and chAntc�tics. They occur generally in fruit, \�etable, outs, seed.
no"'crs, and I.he barfc of trcC They � an inlCifti pan or human djet (Hacl.etl. 1986).
They have b«n reported lO cxlubh. "',de ranac ofbiol�cal ecrecu., &neludina
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et al' ' 1993; Middleton and Kandaswami, 1993; Harwald et al·
J1994;
Balunas and Kinghorn, 2005). Also flavoooids inhibits lipid pcroxidation (LPO) (Salvigre et al, 1988), plo1clc1 aggregation (Gryglewski et al, 1987), and the activity of some enzyme system including cyclo-oxygenase and li poxy geno.sc (1 lopc et al:
1983, Robak et al; 1988). Flovonoids cxe.rt those actions as antioxidants, free radical scavengers and chclators of divalent cations (Cavallini et al; 1978 , Hanasaki, et al;
1994.
Ho":evcr, little is known about the abso rp tion and metabolism of flavonoids 01 the usual level of dietary intake. They ore believed 10 be nontoxic (Middleton &.
Kandas,vomi, 1993) and biologiwly active in ,,n'O and may present free radical mediated cytoloxicity and lipid pcroxidation, which are associated ,vilb eeU ageing and chronic diseases such as atherosclerosis and caniiovosculor damage (Yuting et al; 1990,
Moro et al: 1990) .Mo.ny c,•idcncc suggest that peroxidlltion of LDL is po sitively nssociatcd ,vith athcrogcncsis (1-lcnrikscn et al; 1981, Rankin et al; 1993).
Frnnkcl et al; 1993 rcponed that phenolic compounds (including flavoooids and non flovonoids pol yp bcnols) isolated from red \\-inc inhibit copper calaJ yz ed oxid4tion of LDL Jn vitro. ll is postuJa1cd that the antioxido.nt ond free mdicals scavenging properties of phenolic compounds, present in red ,vine, may exphuo the reduction observed in the coronary hcrut wscasc rote bcl\l.-ccn lhc French populations ,vho consu me ,vine regularly than in other populations despite similar fat intakes (Rimm et al; 1991; RelUlud UNIVERSITY et al; 1992; Frankel et al; 1993 ·>
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2.11 SPONDIAS MO!t£B/N(FAM.JLY: ANACARDIACEA).
2.11.1 Clnssificntion
In document
Abstract Algebra: Theory and Applications
(Page 48-53)