Burning characteristics and emission products related to metallic content in incense

Exposure to incense burning, biomarkers, and the physical health of temple workers in Taiwan

Incense burning releases heavy particulate matter (PM) and nitrogen dioxide (NO2), known to have adverse effects on human health. Long-term exposure to PM and NO2 increases inflammatory cytokine levels and can induce respiratory diseases. This study examined the association between incense burning exposure and the health status, especially inflammatory biomarkers, of temple workers and volunteers in Taiwan. The longitudinal observational study compared adult temple workers and volunteers, with long-term incense burning exposure, to residents from outpatient clinics in the Chiayi area. Forced expiratory volume in 1 s (FEV1) and serum and exhaled breath condensate (EBC) cytokines were assessed. Nonparametric Mann-Whitney U tests were used to compare cytokine levels of the exposure and control groups during the cold and hot weather seasons. FEV1 was significantly more diminished in the exposed group than in the control group during the cold season. Exposure status was associated with greater hot-cold seasonal differences in serum interleukins (IL)-1β (regression coefficient (B) = 6.6, 95% confidence interval (CI) = 5.0 to 8.3, p < .001), IL17-A (B = 2.4, 95% CI = 0.3 to 4.5, p = .03), and plasminogen activator inhibitor [PAI]-1 (B = 5.4, 95% CI = 1.5 to 9.3, p = .009). After adjusting for confounders, the groups' serum levels of IL-1β, IL-17A, and PAI-1 significantly differed. EBC cytokines did not show significant differences. Elevated levels of IL-1β, IL17-A, and PAI-1 have been associated with various autoinflammatory syndromes and diseases. Given the cultural significance of incense burning, culturally sensitive interventions, including education, policy development, and program implementation, are crucial to protect individuals' health, especially temple workers, from the adverse effects of exposure, addressing the manufacture, importation, and sale of incense.

Transformation of hazardous sacred incense sticks ash waste into less toxic product by sequential approach prior to their disposal into the water bodies

Incense sticks ash is one of the most unexplored by-products generated at religious places and houses obtained after the combustion of incense sticks. Every year, tonnes of incense sticks ash is produced at religious places in India which are disposed of into the rivers and water bodies. The presence of heavy metals and high content of alkali metals challenges a potential threat to the living organism after the disposal in the river. The leaching of heavy metals and alkali metals may lead to water pollution. Besides this, incense sticks also have a high amount of calcium, silica, alumina, and ferrous along with traces of rutile and other oxides either in crystalline or amorphous phases. The incense sticks ash, heavy metals, and alkali metals can be extracted by water, mineral acids, and alkali. Ferrous can be extracted by magnetic separation, while calcium by HCl, alumina by sulfuric acid treatment, and silica by strong hydroxides like NaOH. The recovery of such elements by using acids and bases will eliminate their toxic heavy metals at the same time recovering major value-added minerals from it. Here, in the present research work, the effect on the elemental composition, morphology, crystallinity, and size of incense sticks ash particles was observed by extracting ferrous, followed by extraction of calcium by HCl and alumina by H₂SO₄ at 90-95 °C for 90 min. The final residue was treated with 4 M NaOH, in order to extract leachable silica at 90 °C for 90 min along with continuous stirring. The transformation of various minerals phases and microstructures of incense sticks ash (ISA) and other residues during ferrous, extraction, calcium, and alumina and silica extraction was studied using Fourier transform infrared (FTIR), dynamic light scattering (DLS), X-ray fluorescence (XRF), X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), and inductively coupled plasma-optical emission spectroscopy (ICP-OES). DLS was used for analyzing the size during the experiments while FTIR helped in the confirmation of the formation of new products during the treatments. From the various instrumental analyses, it was found that the toxic metals present in the initial incense sticks ash got eliminated. Besides this, the major alkali metals, i.e., Ca and Mg, got reduced during these successive treatments. Initially, there were mainly irregular shaped, micron-sized particles that were dominant in the incense sticks ash particles. Besides this, there were plenty of carbon particles left unburned during combustion. In the final residue, nanosized flowers shaped along with cuboidal micron-sized particles were dominant. present in If, such sequential techniques will be applied by the industries based on recycling of incense sticks ash, then not only the solid waste pollution will be reduced but also numerous value-added minerals like ferrous, silica, alumina calcium oxides and carbonates can be recovered from such waste. The value-added minerals could act as an economical and sustainable source of adsorbent for wastewater treatment in future.

Tanshinone IIA suppresses burning incense-induced oxidative stress and inflammatory pathways in astrocytes

The burning incense (BI) behavior could be widely observed in Asia families. Incense sticks are often believed to be made from natural herbs and powders, and to have minimal impact on human health; however, there is limited research to support this claim. The current study aimed to identify the components of BI within the particulate matter 2.5 µm (PM_2.5) range and explore if BI has bio-toxicity effects on rat astrocytes (CTX-TNA2). The study also examined the protective effects and underlying molecular mechanisms of tanshinone IIA, a primary lipid-soluble compound found in the herb danshen (Salvia miltiorrhiza Bunge), which has been shown to benefit the central nervous system. Results showed that despite the differences in BI components compared to the atmospheric particulate matter (PM) standards, BI still had a bio-toxicity on astrocytes. BI exposure caused early and late apoptosis, reactive oxygen species (ROS) production, MAPKs (JNK, p38, and ERK), and Akt signaling activation, and inflammation-related proteins (cPLA2, COX-2, HO-1, and MMP-9) increases. Our results further exhibit that the tanshinone IIA pre-treatment could significantly avoid the BI-induced apoptosis and inflammatory signals on rat astrocytes. These findings suggest that BI exposure may cause oxidative stress in rat astrocytes and increase inflammation-related proteins and support the potential of tanshinone IIA as a candidate for preventing BI-related adverse health effects.

Heavy metal exposure risk associated with ingestion of Oreochromis niloticus and Coptodon kottae harvested from a lacustrine ecosystem

Lacustrine ecosystems have not been widely assessed for heavy metal contamination and associated health risks; yet, they could be accumulating these contaminants to the detriment of aquatic organisms and communities relying on them for various aspects. The water quality index (WQI) and concentrations of heavy metals including As, Cd, Co, Cu, Cr, Fe, Mn, Ni, Pb, and Zn in water, sediment, Oreochromis niloticus, and in the endemic and endangered Coptodon kottae in Lake Barombi Kotto in Cameroon were determined to evaluate fish heavy metal bioaccumulation, and heavy metal exposure risk posed to communities consuming these fish species. The WQI of the lake was found to be excellent with heavy metal concentrations that were lower than what was obtained in the sediments and fish samples. Mean heavy metal concentrations in sediment ranged from 0.86 ± 0.03 mg/kg for Cd to 560.1 ± 11.15 mg/kg for Fe. In both fish species, Fe, Mn, and Cu had the highest concentrations. Though the heavy metal concentrations in the lake water were low, heavy metal bioconcentration factors for both fish species were very high ranging from 1.6 for Fe to 1568 for Mn. The concentration patterns of heavy metals in the organs of both fish species followed the order bones > gut > muscle. Consumption of these two fish species contributes less than 1.0% of the permissible tolerable daily intake (PTDI) and provisional tolerable weekly intake (PTWI) of these metals with lead (Pb) having the potential to exceed permissible exposure levels when high amounts of these fish are consumed by adults.

Health and Environmental Risks of Incense Smoke: Mechanistic Insights and Cumulative Evidence

Incense burning is practiced alongside many sacred rituals across different regions of the world. Invariable constituents of incense brands are 21% (by weight) herbal and wood powder, 33% bamboo stick, 35% fragrance material, and 11% adhesive powder. Major incense-combustion outputs include particulate matter (PM), volatile organic content, and polyaromatic hydrocarbons. The relative toxicity of these products is an implicit function of particle size and incomplete combustion, which in turn vary for a specific incense brand. Lately, the attention given to the Air Quality Index by international regulatory bodies has created concern about mounting PM toxicity. The uncharacteristically small physical dimensions of these entities complicates their detection, and with no effect of gravity PM fractions rapidly contribute to oxidative stress, enhancing random biochemical reactions upon being inhaled. Incense burning generates four times the PM extent (45 mg•g⁻¹) of cigarettes (~10 mg•g⁻¹). Several poisonous gases, such as CO, CO₂, NO₂, and SO₂, and the unavoidable challenge of disposing of the burnt incense ash further add to the toxicity. Taken together, these issues demonstrate that incense burning warrants prompt attention. The aim of this article is to highlight the toxicity of incense-combustion materials on the environment and human health. This discussion could be significant in framing future policy regarding ecofriendly incense manufacture and reduced usage.

The Adverse Impact of Incense Smoke on Human Health: From Mechanisms to Implications

Incense burning is a very popular activity in daily life among many parts all over the world. A growing body of both epidemiological and experimental evidences has reported the negative effects of incense use on human well-being, posing a potential threat at public significance. This work is a comprehensive review that covers the latest findings regarding the adverse impact of incense smoke on our health, providing a panoramic visualization ranging from mechanisms to implications. The toxicities of incense smoke come directly from its harmful constituents and deposition capacity in the body. Besides, reactive oxygen species-driven oxidative stress and associated inflammation seem to be plausible underlying mechanisms, eliciting various unfavorable responses. Although our current knowledge remains many gaps, this issue still has some important implications.

Estimation of Soil and Dust Ingestion Rates from the Stochastic Human Exposure and Dose Simulation Soil and Dust Model for Children in Taiwan

This study focuses on estimating the probabilistic soil and dust ingestion rates for children under 3 years old by the Stochastic Human Exposure and Dose Simulation Soil and Dust (SHEDS-S/D) model developed by the U.S. Environmental Protection Agency. The health risk of children's exposure to heavy metals through soil and dust ingestion and dermal absorption was then assessed in three exposure scenarios. In the exposure scenario of direct contact with soil, the average soil and dust ingestion rates for children aged 24 to 36 months were 90.7 and 29.8 mg day^-1 in the sand and clay groups, respectively. Hand-to-mouth soil ingestion was identified as the main contributor to soil and dust ingestion rates, followed by hand-to-mouth dust ingestion and object-to-mouth dust ingestion. The soil-to-skin adherence factor was the most influential factor increasing the soil and dust ingestion rate based on a sensitivity analysis in the SHEDS-S/D model. Furthermore, the modeled soil and dust ingestion rates based on the SHEDS-S/D model were coincident with results calculated by the tracer element method. Our estimates highlight the soil ingestion rate as the key parameter increasing the risk for children, while a higher frequency of hand washing could potentially reduce the risk.

Human health-risk assessment based on chronic exposure to the carbonyl compounds and metals emitted by burning incense at temples

Health effects resulting from the smoke of carbonyl compounds (aldehydes and ketones) and metal-containing incense particles at temples during incense burning periods were evaluated at temple A (without incense reduction activities) and B (with incense reduction activities), Nantou County, in 2018. The predominant size fractions of particles were PM₁, PM_1-2.5, and PM_2.5-10 at both temples. The total particle mass at temple A was approximately 1.1 times that of temple B due to incense reduction at temple B. The most abundant metal elements in all particle size fractions at both temples were Fe, Al, and Zn. Metal species of incense smoke are divided into three groups by hierarchical cluster analysis and heatmaps, showing higher metal contents in groups PM₁, PM_18-10, and PM_18-2.5 at temple A. In contrast, higher metal contents were observed in PM_18-10 and PM_2.5-1 at temple B. Most of the carbonyl species were formaldehyde and acetaldehyde, released during incense burning periods, with concentrations ranging from 6.20 to 13.05 μg/m³ at both temples. The total deposited fluxes of particle-bound metals at temples A and B were determined to be 83.00% and 84.82% using the International Commission on Radiological Protection (ICRP) model. Health-risk assessments revealed that the risk values of metals and carbonyls were above recommended guidelines (10^-6) at temple A. Since worshippers and staff are exposed to incense burning environments with poor ventilation over a long period, these toxic organic compounds and metals increase health risks in the respiratory tract. Therefore, incense reduction is important to achieve healthy temple environments.

Household incense burning and infant gross motor development: Results from the Taiwan Birth Cohort Study

BACKGROUND

Air pollution from biomass burning were associated with neurodevelopmental deceleration, but limited studies concerned about the effect of indoor biomass burning. Incense burning is a common household ritual practice in Taiwan, while past studies mainly focused on birth weight and allergic disease.

OBJECTIVES

We aimed to find the association between incense burning exposure and children's neurodevelopment.

METHODS

In Taiwan Birth Cohort Study (TBCS), a nationwide representative birth cohort study, children were assessed upon home interview with structured questionnaires upon six and eighteen months old. Multivariate logistic and Cox proportional hazard regression adjusting confounding factors were applied to explore the odds ratio (OR) and hazard ratio (HR) between household incense burning exposure and caregiver-reported neurodevelopment milestones.

RESULTS

In this study, 15,310 term singletons were included, and household incense burning was associated with delay in gross motor neurodevelopment milestone, such as walking with support (Occasional incense burning: OR = 1.26, 95% confidence interval (CI): 1.08 to 1.47, HR = 1.07, 95% CI: 1.03 to 1.11; persistent incense burning: OR = 1.44, 95% CI: 1.22 to 1.69, HR = 1.11, 95% CI: 1.07 to 1.16) and walking steadily (Occasional incense burning: OR = 1.14, 95% CI: 0.98 to 1.32, HR = 1.07, 95% CI: 1.03 to 1.11, persistent incense burning: OR = 1.24, 95% CI: 1.06 to 1.45, HR = 1.09, 95% CI: 1.04 to 1.13).

CONCLUSIONS

Our study suggested household incense burning exposure was associated with delay in gross motor neurodevelopmental milestones. Further research is warranted to elucidate the possible mechanism and causal relationship.

Physiochemical characteristics of aerosol particles collected from the Jokhang Temple indoors and the implication to human exposure

This paper presents a detailed study on the indoor air pollution in the Jokahng Temple at Tibet Plateau, and its implication to human health. The mean concentrations of PM_1.0 and PM_2.5 were 435.0 ± 309.5 and 483.0 ± 284.9 μg/m³, respectively. The PM_2.5 concentration exceeded the National Ambient Air Quality Standard (75 μg/m³) by 6.4 times. The size-segregated aerosols displayed a bimodal distribution. One peak was observed in the fine mode (0.4-2.1 μm) and the other peak appeared in the coarse mode (2.1-9.0 μm). The concentration of the total size-resolved PM was 794.3 ± 84.9 μg/m³. The mass fraction of coarse particles shared by 41.1%, apparently higher than that reported at low altitudes, probably due to incomplete combustion at Tibet Plateau with hypoxic atmospheric environment. The total concentration of polycyclic aromatic hydrocarbons (PAHs) was 331.2 ± 60.3 ng/m³, in which the concentration of benzo(a)pyrene (BaP) was 18.5 ± 4.3 ng/m³, over ten times higher than the maximum permissible risk value of 1 ng/m³ on account of carcinogenic potency of particulate PAHs through inhalation. PAHs exhibited a trimodal distribution, of which two peaks were observed in the fine mode and one peak in the coarse mode. With the aromatic rings increasing, the peak intensity increased in the fine mode. Na, Ca, Al, Mg and K dominated the elemental mass profiles, and metals displayed a bimodal distribution with a dominant peak in the coarse range. The total PAH deposition flux was 123.6 and 53.1 ng/h for adults and children, respectively. Coarse particles contributed most deposition flux in the head region, while fine particles contribute most deposition flux in the alveolar region. The increment lifetime cancer risk (ILCR) of PAHs ranaged at 10^-5-10^-4, indicating potential cancer risk to human health. The total deposition flux of metals was estimated at 1.4-13.2 ng/h. With the size increasing, deposition flux increased in the head region while decreased in the alveolar region. The highest ILCR of Cr and Ni were 4.9 × 10^-5 and 1.5 × 10^-6, respectively, exceeding the permissible risk of 10^-6. The hazard quotient (HQ) of Fe (10^-5-10^-4) and Zn (10^-6-10^-5) were much lower than the safe level of 1.0, and thus they were not considered as a health concern.

An analysis of human exposure to trace elements from deliberate soil ingestion and associated health risks

Fifty-seven samples of soils commonly ingested in South Africa, Swaziland, Democratic Republic of Congo (DRC), and Togo were analyzed for the concentrations of arsenic (As), cadmium (Cd), cobalt (Co), chromium (Cr), copper (Cu), lead (Pb), manganese (Mn), nickel (Ni), and zinc (Zn) and their bioaccessibility in the human gastrointestinal tract. Bioaccessibility values were used to calculate daily intake, and hazard quotient of each trace element, and chronic hazard index (CHI) of each sample. Carcinogenic risk associated with As and Ni exposure were also calculated. Mean pseudo-total concentrations of trace elements in all samples were 7.2, 83.3, 77.1, 15.4, 28.6, 24.9, 56.1, 2.8, and 26.5 mg/kg for As, Cr, Mn, Co, Ni, Cu, Zn, Cd, and Pb, respectively. Percent bioaccessibility of Pb (13-49%) and Zn (38-56%) were highest among trace elements studied. Average daily intake values were lower than their respective reference doses for ell elements except for Pb in selected samples. Samples from DRC presented the highest health risks associated with trace element exposure with most of the samples having CHI values between 0.5 and 1.0. Some samples had higher than unacceptable values of carcinogenic risk associated with As and Ni exposure. Results indicate low trace element exposure risk from ingesting most of the soil samples.

Adolescent lung function associated with incense burning and other environmental exposures at home

Incense burning is a popular cultural and religious practice, but whether exposure to incense smoke has effects on lung function is unclear. We investigated association between lung function and incense burning exposure and other household exposures in adolescents who participated in a mass asthma-screening program. Information on asthmatic status and associated factors was obtained from parent-completed questionnaires and student-completed video questionnaires. Approximately 10% of students received lung function examinations. Valid lung function data of 5010 students aged 14-16 years in northern Taiwan were analyzed. Forced vital capacity (FVC) and forced expiratory flow in 1 second (FEV₁ ) were compared by incense burning status and other types of exposures for adolescents. Overall, 70.6% of students were exposed to incense smoke at home. The mean FVC and FEV₁ measures were lower among adolescents with daily exposure to incense burning than those without such exposure (P<.05). Sharing bedroom was also associated with decreased FVC and FEV₁ . After controlling for confounding factors, multivariable linear regression analysis with generalized estimation equation showed that FVC was negatively associated with daily exposure to incense burning, sharing a bedroom, and living in a house adjacent to a traffic road. Such associations were also observed in FEV₁ . Daily exposure to incense burning is associated with impaired adolescent lung function.

Characterization of particulate-phase polycyclic aromatic hydrocarbons emitted from incense burning and their bioreactivity in RAW264.7 macrophage

This study investigated the effects of particle-bound polycyclic aromatic hydrocarbons (PAHs) produced from burning three incense types on and their bioreactivity in the RAW 264.7 murine macrophage cell line. Gas chromatography/mass spectrometry was used to determine the levels of 16 identified PAHs. Macrophages were exposed to incense particle extracts at concentrations of 0, 3.125, 6.25, 12.5, 25, 50, and 100 μg/mL for 24 h. After exposure, cell viability and nitric oxide (NO) and inflammatory mediator [tumor necrosis factor (TNF)-α] production of the cells were examined. The mean atomic hydrogen (H) to carbon (C) ratios in the environmentally friendly, binchotan charcoal, and lao shan incenses were 0.69, 1.13, and 1.71, respectively. PAH and total toxic equivalent (TEQ) mass fraction in the incenses ranged from 137.84 to 231.00 and 6.73-26.30 pg/μg, respectively. The exposure of RAW 264.7 macrophages to incense particles significantly increased TNF-α and NO production and reduced cell viability. The cells treated with particles collected from smoldering the environmentally friendly incense produced more NO and TNF-α compared to other incenses. Additionally, the TEQ of fluoranthene (FL), pyrene (Pyr), benzo[a]anthracene (BaA), chrysene (Chr), benzo[b]fluoranthene (BbF), benzo[k]fluoranthene (BkF), benzo[a]pyrene (BaP), indeno[1,2,3-cd]pyrene (INP), dibenz[a,h]anthracene (DBA), and benzo[g,h,i]perylene [B(ghi)P] had a significant correlation (R² = 0.64-0.98, P < 0.05) with NO and TNF-α production. The current findings indicate that incense particle-bound PAHs are biologically active and that burning an incense with a lower H/C ratio caused higher bioreactivity. The stimulatory effect of PAH-containing particles on molecular mechanisms of inflammation are critical for future study.

Heavy metals in soils along unpaved roads in south west Cameroon: Contamination levels and health risks

Soils enriched with heavy metals from vehicular emission present a significant exposure route of heavy metals to individuals using unpaved roads. This study assessed the extent of Cd, Cr, Co, Cu, Ni, Pb and Zn contamination of soils along unpaved roads in Cameroon, and the health risks presented by incidental ingestion and dermal contact with the soils using metal contamination factor (CF) pollution load index, hazard quotients (HQ) and chronic hazard index (CHI). CF values obtained (0.9-12.2) indicate moderate to high contamination levels. HQ values for Cr, Cd and Pb exceeded the reference doses. Moderate health hazard exists for road users in the areas with intense anthropogenic activities and high average daily traffic (ADT) volume according to CHI values (1-4) obtained. The economy and quality of life in cities with unpaved roads could be threatened by health challenges resulting from long-term exposure to heavy metal derived from high ADT volumes.

Incense burning at home and the blood lead level of preschoolers in Taiwan

The growth and intellectual development of children less than 6 years old may be affected by exposure to low levels of lead. To further reduce environmental lead exposure, this study examined possible household-related factors that affect the blood lead levels of Taiwanese children. In total, based on a stratified random sampling strategy, 934 kindergarten students were recruited throughout Taiwan from April to October 2011 after their parents signed a statement of consent. A venous blood sample was drawn from each participant and analyzed for lead content using inductively coupled plasma mass spectrometry. Information on the demographics and household environment of the study subjects was collected by administering a questionnaire (Table 1). The geometric mean lead level in the blood samples of the study subjects was 1.84 μg/dL with a geometric standard deviation of 1.55. The blood lead level was negatively correlated with household income and parental educational levels (p < 0.0001). Study subjects with more siblings also tended to have higher blood lead levels (p < 0.0001). Incense burning in the home, an ethnic tradition, was also identified as a significant factor for increased blood lead levels (p < 0.0003) and demonstrated a dose-dependent relationship with frequency of incense burning at home (p = 0.0022). Because the health effects of low levels of lead exposure have been reported in recent years and because no consensus has been reached regarding a safety threshold for blood lead level in children, any trivial factor is worth investigating to further prevent lead exposure in children. Incense burning at home is a common traditional religious activity in Taiwan; therefore, more study is warranted to further eliminate the lead content in incense and reduce lead exposure for the families who practice this activity.

Genomic profiling of rice roots with short- and long-term chromium stress

Cr(VI) is the most toxic valency form of Cr, but its toxicity targets and the cellular systems contributing to acquisition of tolerance remain to be resolved at the molecular level in plants. We used microarray assay to analyze the transcriptomic profiles of rice roots in response to Cr(VI) stress. Gene ontology analysis revealed that the 2,688 Cr-responsive genes were involved in binding activity, metabolic process, biological regulation, cellular process and catalytic activity. More transcripts were responsive to Cr(VI) during long-term exposure (24 h, 2,097 genes), than short-term exposure (1- and 3-h results pooled, 1,181 genes). Long-term Cr(VI)-regulated genes are involved in cytokinin signaling, the ubiquitin-proteasome system pathway, DNA repair and Cu transportation. The expression of AS2 transcription factors was specifically modulated by long-term Cr(VI) stress. The protein kinases receptor-like cytoplasmic kinase and receptor-like kinase in flowers 3 were significantly upregulated with only short-term Cr(VI) exposure. In addition, 4 mitogen-activated protein kinase kinase kinases, 1 mitogen-activated protein kinase (MAPK) and 1 calcium-dependent protein kinase (CDPK) were upregulated with short-term Cr(VI) treatment. Expression of reactive oxygen species and calcium and activity of MAPKs and CDPK-like kinases were induced with increasing Cr(VI) concentration. These results may provide new insights into understanding the mechanisms of Cr toxicity and tolerance during different stages in rice roots.

Transcriptomic changes and signalling pathways induced by arsenic stress in rice roots

Arsenic (As) is considered the most common toxic metalloid, but its molecular mode of action is not well understood. We investigated whether arsenate [As(V)] can induce intracellular reactive oxygen species production and calcium oscillation in rice roots. To better understand the molecular basis of plant cell responses to As, we performed a large-scale analysis of the rice transcriptome during As(V) stress. As(V) induced genes involved in abiotic stress, detoxification pathways and secondary metabolic process. Genes involved in secondary cell wall biogenesis, cell cycle and oligopeptide transport were mainly downregulated. Genes encoding signalling components such as receptor-like cytoplasmic kinases protein kinase, APETALA2/ethylene response factor, heat shock factor, MYB and zinc-finger protein expressed in inflorescence meristem transcription factors were increased in expression. The expression of GARP-G2-like and C3H transcription factors was specifically modulated by As(V) stress. The predominant families of As(V)-regulated transporters belonged to the ATP-binding cassette superfamily and telurite-resistance/dicarboxylate transporters. Several factors involved in signaling, such as mitogen-activated protein kinase (MAPK), MAPK kinase kinase and calcium-dependent protein kinase (CDPK), were also upregulated. Moreover, As(V) markedly increased the activity of MAPKs and CDPK-like kinases, and CDPK and NADPH oxidases were involved in As-induced MAPK activation. Further characterization of these As(V)-responsive genes and signalling pathways may help better understand the mechanisms of metalloid uptake, tolerance and detoxification in plants.

Mercury-induced biochemical and proteomic changes in rice roots

Mercury (Hg) is a serious environmental pollution threats to the planet. Accumulation of Hg in plants disrupts many cellular-level functions and inhibits growth and development, but the mechanism is not fully understood. We investigated cellular, biochemical and proteomic changes in rice roots under Hg stress. Root growth rate was decreased and Hg, reactive oxygen species (ROS), and malondialdehyde (MDA) content and lipoxygenase activity were increased significantly with increasing Hg concentration in roots. We revealed a time-dependent alteration in total glutathione content and enzymatic activity of superoxide dismutase (SOD), ascorbate peroxidase (APX), catalase (CAT) and peroxidase (POD) during Hg stress. 2-D electrophoresis revealed differential expression of 25 spots with Hg treatment of roots: 14 spots were upregulated and 11 spots downregulated. These differentially expressed proteins were identified by ESI-MS/MS to be involved in cellular functions including redox and hormone homeostasis, chaperone activity, metabolism, and transcription regulation. These results may provide new insights into the molecular basis of the Hg stress response in plants.

Characterization of polycyclic aromatic hydrocarbon emissions in the particulate phase from burning incenses with various atomic hydrogen/carbon ratios

Polycyclic aromatic hydrocarbons in the particulate phase generated from burning various incense was investigated by a gas chromatography/mass spectrometry. Among the used incenses, the atomic H/C ratio ranged from 0.51 to 1.69, yielding the emission factor ranges for total particulate mass and PAHs of 4.19-82.16 mg/g and 1.20-9.50 μg/g, respectively. The atomic H/C ratio of the incense was the key factor affecting particulate mass and the PAHs emission factors. Both the maximum emission factor and the slowest burning rate appear at the H/C ratio of 1.57. The concentrations of the four-ring PAHs predominated and the major species among the 16 PAHs were fluoranthene, phenanthrene, pyrene, and chrysene for most incense types. The benzo[a]pyrene, benzo[a]anthracene, benzo[b]fluoranthene, and dibenzo[a,h]anthracene accounted for 87.08-93.47% of the total toxic equivalency emission factor.

Toxic emissions from open burning

This review compiled the data from recent actual and simulation studies on toxic emissions from open burning and categorized into sources, broadly as biomass and anthropogenic fuels. Emission factors, in mass of pollutant per mass of material being burned, and actual concentrations, in mass of pollutant per unit volume have been compared based on source classifications. In addition to gaseous emissions, this review presents the updated data on emissions to air in the form of particulate matter, and emissions to soil and water environment. Data from forest fires, accidental fires such as vehicle fires, house fires, and unintentional landfill fires are included in this review as well as combustion involving traditional and recreational activities.

A study of particulates and metallic element concentrations in temple

Concentrations of ambient suspended particulates were measured at Tzu Yun Yen temple in Taiwan (120 degrees , 34', 46.2''E, 24 degrees , 16', 17.1''N), where semi-open incense burning is characteristic. Many pilgrims from different areas with various beliefs visit the temple and burn incense. Samples were collected with a universal sampler used for measuring suspended particulate concentrations. Sampling period was from August 8, 2006, to October 6, 2006. The average PM(10) concentrations measured at the temple were 16% higher than 125 microg/m(3) (this value is the outdoor air quality standard according to Taiwan Environmental Protection Administration (EPA)). In coarse particulates (PM(2.5-10)), the mean metallic elements concentrations are in the order of Ca>Mg>Zn>Fe>Mn>Cr>Cu>Pb during weekend and weekday sampling. In addition, the fine particulates (PM(2.5)) mean metallic elements concentrations are in the order of Ca>Mg>Fe>Zn>Cr>Mn>Pb>Cu during weekend sampling and Ca>Fe>Mg>Zn>Cr>Mn>Pb>Cu during weekday sampling.

Incidence of nasopharyngeal carcinoma in Chinese immigrants, compared with Chinese in China and South East Asia: review

Objectives:

To evaluate the literature and to compare published data on age-standardised incidence rates of nasopharyngeal carcinoma in Chinese people living in and outside China.

Design:

Systematic review of incidence rate studies and statistical incidence data concerning nasopharyngeal carcinoma in Chinese populations from 1960 to 2008.

Data sources:

Sixteen papers were identified from the PubMed, Embase and Scopus electronic databases and from a hand search of the reference lists of the retrieved papers. Further searches for raw data on age-specific and age-standardised incidence rates of nasopharyngeal carcinoma were conducted. Textbooks on relevant subjects were referred to for background information. A total of 19 papers met the inclusion criteria.

Results:

Seven studies included raw data on age-specific and age-standardised incidence rates of nasopharyngeal carcinoma in Chinese people. Twelve other studies reported on changes in the incidence of nasopharyngeal carcinoma in Chinese populations in selected countries or regions. Studies on age-specific and age-standardised rates obtained data from individual registries. Studies on incidence rates obtained data from hospital records, cancer notifications (from all sections of the medical profession), pathology records and death certificates. The results showed a decline in age-standardised incidence rates of nasopharyngeal carcinoma in Chinese immigrant populations, compared with Chinese people in China. There was also a trend towards decreasing incidence the further the population had immigrated. Thus, the incidence of nasopharyngeal carcinoma in Singaporean Chinese was higher than that in Hawaiian Chinese, and that in Hawaiian Chinese was higher than that in Californian Chinese.

Conclusion:

This review found a decreasing trend in the incidence of nasopharyngeal carcinoma in Chinese migrants living in countries with a low risk of the disease.

Incense smoke: clinical, structural and molecular effects on airway disease

In Asian countries where the Buddhism and Taoism are mainstream religions, incense burning is a daily practice. A typical composition of stick incense consists of 21% (by weight) of herbal and wood powder, 35% of fragrance material, 11% of adhesive powder, and 33% of bamboo stick. Incense smoke (fumes) contains particulate matter (PM), gas products and many organic compounds. On average, incense burning produces particulates greater than 45 mg/g burned as compared to 10 mg/g burned for cigarettes. The gas products from burning incense include CO, CO₂, NO₂, SO₂, and others. Incense burning also produces volatile organic compounds, such as benzene, toluene, and xylenes, as well as aldehydes and polycyclic aromatic hydrocarbons (PAHs). The air pollution in and around various temples has been documented to have harmful effects on health. When incense smoke pollutants are inhaled, they cause respiratory system dysfunction. Incense smoke is a risk factor for elevated cord blood IgE levels and has been indicated to cause allergic contact dermatitis. Incense smoke also has been associated with neoplasm and extracts of particulate matter from incense smoke are found to be mutagenic in the Ames Salmonella test with TA98 and activation. In order to prevent airway disease and other health problem, it is advisable that people should reduce the exposure time when they worship at the temple with heavy incense smokes, and ventilate their house when they burn incense at home.