Draft Genome Sequence of Manganese-Oxidizing Bacterium Massilia sp. Strain Mn16-1_5, Isolated from Serpentine Soil in Taitung, Taiwan.

Massilia sp. strain Mn16-1_5 was isolated from serpentine soil. This strain is able to oxidize manganese and has the potential for bioremediation of chromium. Here, we present a 5.53-Mb draft genome sequence of this strain with a G+C content of 64.8% that might provide more information for species delineation and oxidase genes in this strain.

On the use of a freeze-dried versus an air-dried soil humic acid as a surrogate of soil organic matter for contaminant sorption.

The sorption of phenanthrene (PHN) to relatively pure soil humic acids (HAs) was investigated to assess the suitability of the soil HA as a surrogate sorbent for the soil organic matter (SOM). The HAs were prepared in both freeze-dried and air-dried forms. The two forms of HAs from the same source are similar in composition but the freeze-dried HAs exhibit a significantly higher initial surface area (SA) (3.86-4.59 m(2)/g); the SAs of air-dried HAs are below 0.1 m(2)/g. However, the SAs of freeze-dried HAs are not stable upon contact with water; the samples lose practically all the SA after 4 days of immersion in water. The PHN sorption to both forms of HAs is practically linear, whether a co-solute is present or not. The sorption linearity observed with the present freeze-dried HAs is in sharp contrast with the allegedly nonlinear PHN sorption on similar freeze-dried HAs as presented by others.

Effect of traffic loading on particle-bound water-soluble ions and carbons collected near a busy road and at an urban site.

This study examines size-resolved particle-bound water-soluble ions and carbons (element carbon (EC) and organic carbon (OC)) collected near a busy road and at an urban site. The traffic-related fine and coarse particles were collected using two manual dichotomous samplers (Dichots) equipped with Quartz filters. The PM(2.5)/PM(2.5-10) value during rush hour (3.57) exceeded that during slack time (2.72). During weekdays and weekends, although the roadside PM(2.5) concentration correlated well with traffic flow (R(2)= 0.91 and 0.81, respectively), the roadside PM(2.5-10) concentration did not. The lowest second aerosol concentrations were observed from 19:00 to 21:00 during weekdays and weekends. The average content of total water-soluble ions in PM(2.5) was 30.7% and 35.7% for weekday and weekend samples, respectively (a total average of 33.2%). In PM(2.5), the content of NO(3)(-) (8.95-11.0%) exceeded that of SO(4)(2-) (7.08-8.10%) at the roadside site. Conversely, the content of PM(2.5)-bound SO(4)(2-) was higher than that of PM(2.5)-bound NO(3)(-) at the urban site. The mean content of PM(2.5)-bound TC was 35.8%, while that of PM(2.5-10)-bound TC was 15.9%. Moreover, the R(2) values of traffic flow versus PM(2.5)-bound EC concentration on weekdays and weekends were 0.89 and 0.56, respectively, and were 0.82 and 0.38, respectively, for those of traffic flow versus PM(2.5)-bound OC concentration.

Characteritization of, and health risks from, polychlorinated dibenzo-p-dioxins/dibenzofurans from incense burned in a temple.

Polychlorinated dibenzo-p-dioxins/dibenzofurans (PCDD/Fs) may cause adverse health effects. However, PCDD/F emissions from burning incense in temples have rarely been addressed. This study investigates PCDD/F emissions from burning incense in a temple. The mean total PCDD/F concentrations were 72.4-82.2 pg Nm(-3) at two indoor sites; their corresponding mean total PCDD/Fs I-TEQ concentrations (0.24-0.27 pg I-TEQ Nm(-3)) were approximately 11 times that at a background location. In air samples collected from burning incense, OCDFs accounted for approximately 90% of total PCDD/Fs at the two indoor sites and an outdoor site near the temple, while the major PCDD/Fs in incense ash were PCDDs. The total PCDD/F content and toxic equivalent value of incense ash were 617 pg g(-1) and 1.55 pg I-TEQ g(-1), respectively. At the three sites inside/outside the temple, the air and ash samples contained the same four primary PCDD/Fs-OCDD, 1,2,3,4,6,7,8-HpCDD, OCDF and 1,2,3,4,6,7,8-HpCDF. The Cl- emission factor, which is related to the PCDD/F formation, from burning incense was 0.454 mg g(-1). The resultant lifetime average daily dose and cancer risk for temple workers were 0.00964 pg I-TEQ day(-1) kg(-1) and 9.64 x 10(-6), respectively, approximately 2 times that for residents near the temple (0.00489 pg I-TEQ day(-1) kg(-1) and 4.89 x 10(-6), respectively). We suggest that the chlorine content in incense must be regulated, and the high risk of PCDD/F exposure from burning incense for temple workers and visitors should be of concern.

Reaction efficiencies and rate constants for the goethite-catalyzed Fenton-like reaction of NAPL-form aromatic hydrocarbons and chloroethylenes.

The contaminants present as nonaqueous phase liquids (NAPLs) in the subsurface are long-term sources for groundwater pollution. Fenton-like reaction catalyzed by natural iron oxides such as goethite in soils is one of the feasible in situ chemical reactions used to remediate contaminated sites. This research evaluated the Fenton-like reaction of five chlorinated ethylenes and three aromatic hydrocarbons using goethite as the catalyst. The reaction efficiencies and rate constants of these compounds in NAPL and dissolved forms were compared. The content of goethite used in batch experiments was in the range similar to those found in subsurfaces. Low H2O2 concentrations (0.05 and 0.1%) were tested in order to represent the low oxidant concentration in the outer region of treatment zone. The results showed that at the tested goethite and H2O2 ranges, the majority of contaminants were removed in the first 120 s. When aromatics and chloroethylenes were present as NAPLs, their removal efficiencies and reaction constants decreased. The removal efficiencies of 0.02 mmol NAPL contaminants were 26-70% less than those of the dissolved. The measured rate constants were in the order of 10(9) M(-1) s(-1) for dissolved chlorinated ethylenes and aromatic hydrocarbons, but were 25-60% less for their NAPL forms. The initial dosage of H2O2 and NAPL surface areas (18.4-38.2 mm2) did not significantly affect reaction efficiencies and rate constants of chlorinated NAPLs. Instead, they were related to the octanol-water partition coefficient of compounds. For both dissolved and NAPL forms, aromatic hydrocarbons were more reactive than chlorinated ethylenes in Fenton-like reaction. These results indicated that the decrease in reaction efficiencies and rate constants of NAPL-form contaminants would pose more negative impacts on the less reactive compounds such as benzene and cis 1,2-DCE during goethite-catalyzed Fenton-like reaction.

Water-soluble ions in nano/ultrafine/fine/coarse particles collected near a busy road and at a rural site.

This study investigated water-soluble ions in the sized particles (particularly nano (PM(0.01-0.056))/ultrafine (PM(0.01-0.1))) collected using MOUDI and Nano-MOUDI samplers near a busy road site and at a rural site. The analytical results demonstrate that nano and coarse particles exhibited the highest (16.3%) and lowest (8.37%) nitrate mass ratios, respectively. The mass ratio of NO(3)(-) was higher than that of SO(4)(2-) in all the sized particles at the traffic site. The secondary aerosols all displayed trimodal distributions. The aerosols in ultrafine particles collected at the roadside site exhibited Aitken mode distributions indicating they were of local origin. This finding was not observed for those ultrafine particles collected at the rural site. The mass median diameters (MMDs) of the nano, ultrafine, and fine particles were smaller at the traffic site than at the rural site, possibly related to the contribution of mobile engine emissions.