Bs. De Martinis et al., Genotoxicity of fractionated organic material in airborne particles from Sao Paulo, Brazil, MUT RES-GTE, 446(1), 1999, pp. 83-94
Citations number
41
Categorie Soggetti
Molecular Biology & Genetics
Journal title
MUTATION RESEARCH-GENETIC TOXICOLOGY AND ENVIRONMENTAL MUTAGENESIS
Particulate matter less than 10 mu m aerodynamic diameter (PM10) is associa
ted with adverse health effects including increased respiratory problems an
d mortality. PMIO is also associated with increases in cancer in some urban
areas. Identification of toxic compounds in PM10 is a step toward estimati
ng exposure to these compounds and evaluating their public health risk. How
ever, the toxic compounds on PM10 are part of a highly complex mixture of c
ompounds that makes chemical characterization difficult. Before this study,
there has been little investigation of genotoxic compounds in particulate
matter from Latin American cities. Here, both bioassay (mutagenicity) and c
hemical analyses were conducted with organic solvent extracts of PM10 colle
cted from Sao Paulo, a major Brazilian city. Sequential extraction in dichl
oromethane (DCM) followed by acetone (ACE) yielded 20.3% and 10.2% of the t
otal mass, respectively. Non-polar and moderately polar organic material so
lubilized in DCM. ACE extracted more polar organic species and some inorgan
ic ions. Both extracts were fractionated separately using cyanopropyl-bonde
d silica chromatography with organic solvents of increasing polarity. The m
ass distribution among the fractions was measured. The mutagenic activity o
f the fractions was assayed using the microsuspension procedure with the Sa
lmonella typhimurium tester strain TA98, with and without addition of metab
olic enzymes (S9). The DCM extract had about four times higher mutagenic ac
tivity than the ACE extract. In general, addition of S9 resulted in an incr
ease in mutagenicity of DCM fractions, but a decrease for the ACE extract.
Most of the activity was concentrated in fractions in the mid-range of pola
rity within both the DCM and ACE extracts. The fractions were analyzed by g
as chromatography with mass selective detection (GC/MS) without derivatizat
ion. The most mutagenic fractions in the DCM extract contained ketones, ald
ehydes, and quinolines. The most mutagenic ACE fraction had ketones, carbox
ylic acids, and aldehydes. (C) 1999 Elsevier Science B.V. All rights reserv
ed.