This study investigated the eco-physiological changes in the eggplant and common bean caused by the simultaneous fumigation of ozone (O₃) and Phenanthrene (PHE) for more than 30 days. The eggplant and common bean leaves were individually exposed or in combination with 120 ppbv O₃ and 10 µM PHE inside open top chambers. The treatments negatively affected the net photosynthetic rate at near-saturating irradiance, stomatal conductance, photochemical efficiency of PS II in the dark, and chlorophyll content. The foliar symptom assessments of chlorosis and reddish brown stippling revealed severe damage due to the O₃ and PHE treatments. The photosynthetic rate was considered to be affected by a reduction in the stomatal function and ingredient content of the leaf. Mannitol (a reactive oxygen scavenger) mitigated the effects of the treatments; thus, reactive oxygen species generated through O₃ and PHE may be responsible for the damaged plants.

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High concentrations of PM_2.5 were observed in the Kanto area from November 2–6, 2011. The PM_2.5 concentrations were compared from all over Japan, and high concentrations were only observed in the Kanto area. Therefore, this episode was mainly caused not by long-range transport or trans-boundary pollution, but by local pollution. The atmosphere was generally stagnant during this period, and the atmospheric stability was stable on November 3–4 due to the formation of an inversion layer, and was neutral on November 5–6. These conditions were one of the reasons for this episode. NO₃^- and OC were dominantly high among the observed chemical species in the PM_2.5. NO₃^- was particularly high on November 5–6 probably due to remarkable HNO₃ production from NO under a very high humidity condition during the nighttime. NO was also irregularly high on November 3–4, which possibly implies the influence of the combustion of agricultural residues (biomass burning). The chemical species indicators of biomass burning such as K⁺, char-EC, and levoglucosan were also high. Thus it was suggested that the influence of biomass burning on the PM_2.5 was predominant during this period. However, the influence of fossil fuel burning was observed in the southern part of the Kanto area based on the SO₄^2- and V. Although the PM_2.5 concentration is measured by methods decreasing the water content, it was estimated that the water content affected the high concentration of the observed PM_2.5 during this period in comparison to the reconstructed PM_2.5 concentration from the main chemical species.

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Continuous formaldehyde (HCHO) measurements by the fluorometric (Hantzsch reaction) method have been carried out at a point in the eastern part of the Tokyo Metropolitan Area, which was significantly influenced by many pollution sources from June 2010 to January 2013. In 2012, the average of the daily average concentrations was 3.03 ppbv, the 98 percentile value was 6.90 ppbv and the maximum concentration was 9.99 ppbv (n=318). Based on hourly averages, the median was 2.47 ppbv, the maximum was 29.7ppbv and the geometric average was 2.55 ppbv (n=7776). For the frequency distributions of the hourly averaged HCHO, the peaks decreased in the range of 1 to 2 ppbv. The hourly average concentration showed an approximate log-normal distribution. We presumed source attributions of 76 peak events over 20 ppbv (1-min average) as follows: 8 events correlated with CO indicating their sources were primary emissions from combustion-related stationary sources, 1 event correlated with SO₂ indicating its source was the primary emission from ships in Tokyo Bay, 31 events having a low correlation with CO, SO₂ and O₃ indicating their sources were the primary emission from not-combustion-related stationary sources, 28 events correlated with O₃ indicating they were due to the secondary formation by VOC emitted from not-combustion-related stationary sources, and 8 events correlated with both CO and O₃ indicating they were due to both the primary emission and the secondary formation. These peak HCHO events were presumed to be highly influenced by the stationary sources in the neighborhood of this area.

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