OZONE PRECURSOR VOLATILE ORGANIC COMPOUNDS (HYDROCARBONS AND CARBONYLS): ANALYSIS OF THE POTENTIAL FOR OZONE FORMATION AND HEALTH EFFECTS IN URBAN AREA
Name: Mayana Rigo Alves
Type: PhD thesis
Publication date: 21/09/2022
Advisor:
Name | Role |
---|---|
Neyval Costa Reis Jr. | Advisor * |
Examining board:
Name | Role |
---|---|
Thiago Nogueira | External Examiner * |
Neyval Costa Reis Jr. | Advisor * |
Maria de Fátima Andrade | External Examiner * |
Jane Meri Santos | Internal Examiner * |
Elson Silva Galvão | Co advisor * |
Elisa Valentim Goulart | Internal Examiner * |
Summary: High concentration of tropospheric ozone (O3) is a significant problem worldwide, as it is
associated with damage to physical and mental health, increase in premature deaths,
agricultural losses and climate change. Since ozone is a secondary pollutant, control actions
are indirect, acting on its precursors. Each volatile organic compound (VOC) acting as a
precursor of ozone formation has its individual incremental reactivitie (IR), therefore,
different ozone formation potential (OFP). The general objective of this work is study the
concentrations of VOC precursors of ozone in the atmosphere, calculate your PFO using the
MIR scale and investigate possible concentration exceedance limits that could cause harm to
human health. To reach the presented goal, 3 specific objectives were designed for this study.:
(i) conducting a systematic literature review on ozone precursors and OFP, (ii) assessment of
potential harmful health effects related to VOC concentrations in bus terminals and (iii)
assessment of the OFP of the volatile organic compounds (VOC) present in the atmosphere of
the city of Vitória and its daily time variation. The results indicate that all concentrations
observed in the terminals (except 1 of them) exceeded the value of 4.0 µg/m3
for
formaldehydes (F) of the Agency for Toxic Substances and Disease Registry ATSDR
(USEPA, 2016) threshold for the minimum level of risk reference limit. And one of the
terminals exceeded the limit of 9 µg/m3 for acetaldehydes (A). Regarding the evaluation of the
OFP the urban area of Vitória-ES for BTX and aldehydes, the F and A data were very high in
relation to other Brazilian cities, and the calculated F/A ratio was 2.5. Acetaldehyde came
closer to the NO2 variation curve than F, and showed a significant variation of its high
concentrations with respect to rush hour. While the data from F did not demonstrate to follow
the hourly profile of vehicular emissions. BTX data are more closely related to vehicular
emissions, however, the maximum concentrations of xylenes demonstrate industrial influence.
The BTX have their highest PFO value at 9 am and can influence the formation of 41% of the
maximum O3 value of the day. The average found for benzene in Vitória was 0,16 µg/m3
,
within the USEPA`s, one-in-a-million chance of developing cancer.