Haloacetic acids in swimming pool and spa water in the United States and China

The objective of this study is to investigate the occurrence of haloacetic acids （HAAs）, a group of disinfection byproducts, in swimming pool and spa water. The samples were collected from six indoor pools, six outdoor pools and three spas in Pennsylvania, the United States, and from five outdoor pools and nine indoor pools in Beijing, China. Five HAAs （HAA5）, including monochloroacetic acid, dichloroacetic acid, trichloroacetic acid, monobromoacetic acid, and dibromoacetic acid were analyzed. Total chlorine, pH and total organic carbon concentration were analyzed as well. Results indicated that the levels of HAA5 in swimming pools and spas in the United States ranged from 70 to 3980μg·L^-1, with an arithmetic average at 1440μg·L^-1 and a median level at 1150μg·L^-1. These levels are much higher than the levels reported in chlorinated drinking water and are likely due to organic matters released from swimmers＇ bodies. The levels of HAA5 in swimming pools in China ranged from 13 to 332μg·L^-1, with an arithmetic average at 117μg·L^-1 and a median level at 114μg·L^-1. The lower HAA levels in swimming pools in China were due to the lower chlorine residuals. Results from this study can help water professionals to better understand the formation and stability of HAAs in chlorinated water and assess risks associated with exposures to HAAs in swimming pools and spas.     

Characteristics of typical dissolved black carbons and their influence on the formation of disinfection by-products in chlor(am)ination

● The physicochemical and structural properties of DBC were characterized. ● The effects of DBC on DBPs and DBPFP generation during disinfection were evaluated. ● The DBPs and DBPFP generation during chlor(am)ination were compared. Dissolved black carbon (DBC) released from biochar can be one of the potential disinfection by-products (DBPs) precursors in the dissolved organic matter pool. However, the physiochemical and structural properties of DBC and the effects on the development of DBPs and DBP formation potential (DBPFP) during the disinfection process remain unclear. In this study, the characteristics of two kinds of DBC, namely, animal-derived DBC (poultry litter DBC, PL-DBC) and plant-derived DBC (wheat straw DBC, WS-DBC), were investigated. The effects of different kinds of DBC on the evolution of DBPs and DBPFP in chlorine and chloramine disinfection processes were compared with natural organic matter (NOM). The results showed that the total DBPs concentrations derived from PL-DBC, WS-DBC and NOM were similar during chlorination (i.e., 61.23 μg/L, 64.59 μg/L and 64.66 μg/L, respectively) and chloramination (i.e., 44.63 μg/L, 44.42 μg/L and 45.58 μg/L, respectively). The lower total DBPs and DBPFP concentrations in chloramination could be attributed to the fact that the introduction of ammonia in chloramine inhibited the breaking of the bond between the disinfectant and the active group of the precursor. Additionally, DBC presented much lower total DBPFP concentrations than NOM in both chlorination and chloramination. However, both kinds of DBC tended to form more monochloroacetic acids and haloacetamides than NOM, which could result from the higher organic strength, higher protein matter, and nitrogen-rich soluble microbial products of DBC.     

饮用水中卤乙酸和三卤甲烷的形成及影响因素研究

以浙江省钱塘江流域的七种水源水为代表，分析了前体物、pH值、投氯量、氯化时间和温度等因素对氯化消毒副产物(DBPs)中三种卤乙酸(HAAs)和三种三卤甲烷(THMs)的影响，研究表明，总有机碳(TOC)和UV-254与HAAs前体物呈正相关，而与THMs前体物的相关性较差；在pH5-10的范围内，pH值对HAAs的形成影响较小，pH值愈高HAAs总量愈小，而对THMs的形成影响较大，THMs总量随pH值的增高而增大；HAAs和THMs的形成量与投氯量、氯化时间均呈正相关；在正常气温条件下，随温度的增加而增加。     

Disinfection byproducts in drinking water and regulatory compliance: A critical review

Disinfection by-products (DBPs) are regulated in drinking water in a number of countries. This critical review focuses on the issues associated with DBP regulatory compliance, including methods for DBP analysis, occurrence levels, the regulation comparison among various countries, DBP compliance strategies, and emerging DBPs. The regulation comparison between China and the United States (US) indicated that the DBP regulations in China are more stringent based on the number of regulated compounds and maximum levels. The comparison assessment using the Information Collection Rule (ICR) database indicated that the compliance rate of 500 large US water plants under the China regulations is much lower than that under the US regulations (e.g. 62.2% versus 89.6% for total trihalomethanes). Precursor removal and alternative disinfectants are common practices for DBP regulatory compliance. DBP removal after formation, including air stripping for trihalomethane removal and biodegradation for haloacetic acid removal, have gained more acceptance in DBP control. Formation of emerging DBPs, including iodinated DBPs and nitrogenous DBPs, is one of unintended consequences of precursor removal and alternative disinfection. At much lower levels than carbonaceous DBPs, however, emerging DBPs have posed higher health risks.     

Formation of disinfection by-products during sodium hypochlorite cleaning of fouled membranes from membrane bioreactors

•HAAs was dominant among the DBPs of interest. •Rising time, dose, temperature and pH raised TCM and HAAs but reduced HANs and HKs. •Low time, dose and temperature and non-neutrality pH reduced toxic risks of DBPs. •The presence of EPS decelerated the production of DBPs. •EPS, particularly polysaccharides were highly resistant to chlorine. Periodic chemical cleaning with sodium hypochlorite (NaClO) is essential to restore the membrane permeability in a membrane bioreactor (MBR). However, the chlorination of membrane foulants results in the formation of disinfection by-products (DBPs), which will cause the deterioration of the MBR effluent and increase the antibiotic resistance in bacteria in the MBR tank. In this study, the formation of 14 DBPs during chemical cleaning of fouled MBR membrane modules was investigated. Together with the effects of biofilm extracellular polymeric substances (EPS), influences of reaction time, NaClO dosage, initial pH, and cleaning temperature on the DBP formation were investigated. Haloacetic acids (HAAs) and trichloromethane (TCM), composed over 90% of the DBPs, were increasingly accumulated as the NaClO cleaning time extended. By increasing the chlorine dosage, temperature, and pH, the yield of TCM and dichloroacetic acid (DCAA) was increased by up to a factor of 1‒14, whereas the yields of haloacetonitriles (HANs) and haloketones (HKs) were decreased. Either decreasing in the chlorine dosage and cleaning temperature or adjusting the pH of cleaning reagents toward acidic or alkaline could effectively reduce the toxic risks caused by DBPs. After the EPS extraction pretreatment, the formation of DBPs was accelerated in the first 12 h due to the damage of biofilm structure. Confocal laser scanning microscopy (CLSM) images showed that EPS, particularly polysaccharides, were highly resistant to chlorine and might be able to protect the cells exposed to chlorination.     

Identification of important precursors and theoretical toxicity evaluation of byproducts driving cytotoxicity and genotoxicity in chlorination

• NOM formed more C-DBPs while amino acids formed more N-DBPs during chlorination • Aspartic acid and asparagine showed the highest toxicity index during chlorination • Dichloroacetonitrile might be a driving DBP for cytotoxicity and genotoxicity • Dichloroacetonitrile dominated the toxicity under different chlorination conditions Chlorination, the most widely used disinfection process for water treatment, is unfortunately always accompanied with the formation of hazardous disinfection byproducts (DBPs). Various organic matter species, like natural organic matter (NOM) and amino acids, can serve as precursors of DBPs during chlorination but it is not clear what types of organic matter have higher potential risks. Although regulation of DBPs such as trihalomethanes has received much attention, further investigation of the DBPs driving toxicity is required. This study aimed to identify the important precursors of chlorination by measuring DBP formation from NOM and amino acids, and to determine the main DBPs driving toxicity using a theoretical toxicity evaluation of contributions to the cytotoxicity index (CTI) and genotoxicity index (GTI). The results showed that NOM mainly formed carbonaceous DBPs (C-DBPs), such as trichloromethane, while amino acids mainly formed nitrogenous DBPs (N-DBPs), such as dichloroacetonitrile (DCAN). Among the DBPs, DCAN had the largest contribution to the toxicity index and might be the main driver of toxicity. Among the precursors, aspartic acid and asparagine gave the highest DCAN concentration (200 g/L) and the highest CTI and GTI. Therefore, aspartic acid and asparagine are important precursors for toxicity and their concentrations should be reduced as much as possible before chlorination to minimize the formation of DBPs. During chlorination of NOM, tryptophan, and asparagine solutions with different chlorine doses and reaction times, changes in the CTI and GTI were consistent with changes in the DCAN concentration.     

Impact of total organic carbon and chlorine to ammonia ratio on nitrification in a bench-scale drinking water distribution system

Nitrification occurs in chloraminated drinking water systems and is affected by water quality parameters. The aim of this study was to investigate the impact of total organic carbon and chlorine to ammonia ratio on nitrification potential in a simulated drinking water distribution system as during chloramination. The occurrence of nitrification and activity of nitrifying bacteria was primarily monitored using four rotating annular bioreactors (RAB) with different chlorine to ammonia ratios and total organic carbon (TOC) levels. The results indicated that nitrification occurred despite at a low influent concentration of ammonia, and a high concentration of nitrite nitrogen was detected in the effluent. The study illustrated that reactors 1(R1) and 3 (R3), with higher TOC levels, produced more nitrite nitrogen, which was consistent with the ammonia-oxidizing bacteria (AOB) counts, and was linked to a relatively more rapid decay of chloramines in comparison to their counterparts (R2 and R4). The AOB and HPC counts were correlated during the biofilm formation with the establishment of nitrification. Biofilm AOB abundance was also higher in the high TOC reactors compared with the low TOC reactors. The chlorine to ammonia ratio did not have a significant impact on the occurrence of nitrification. Bulk water with a high TOC level supported the occurrence of nitrification, and AOB development occurred at all examined chlorine to ammonia dose ratios (3:1 or 5:1).     

Unlocked disinfection by-product formation potential upon exposure of swimming pool water to additional stimulants

• Swimming pool water was studied for DBPs upon exposure to additional stimulants. • DBP formation could be induced by residual chlorine and extended incubation. • Urine led to a massive formation of chloroform with additional stimulants. • Reactions between chlorine and anthropogenic organics were slow and long-lasting. • Urine control and air ventilation should be on the priority list for pool management. Anthropogenic organics are known to be responsible for the formation of harmful disinfection by-products (DBPs) in swimming pool water (SPW). The research explored an important scenario of SPW with no additional anthropogenic organic input. With stimulations by residual chlorine or additional chlorine and extended incubation, the formation of DBPs, especially chloroform, was significantly induced. Similar observations were found by investigating synthetic SPW made with sweat and urine. The presence of urine led to a massive formation of chloroform, as noted by an approximate 19-fold increase after 165-day incubation with a shock chlorine dose. The research suggests that consistent residual chlorine and long water retention as two typical features of SPW could unlock the DBP formation potential of anthropogenic organics. Thus, limiting the introduction of anthropogenic organics may not have an immediate effect on reducing DBP levels, because their reactions with chlorine can be slow and long-lasting. Pool management should prioritize on control of urine and improving air ventilation. This work is useful to deepen understandings about DBP formation in SPW and provide implications for pool management and prospective legislation.     

Whole pictures of halogenated disinfection byproducts in tap water from China’s cities

When bromide/iodide is present in source water, hypobromous acid/hypoiodous acid will be formed with addition of chlorine, chloramine, or other disinfectants. Hypobromous acid/hypoiodous acid undergoes reactions with natural organic matter in source water to form numerous brominated/iodinated disinfection byproducts (DBPs). In this study, tap water samples were collected from eight cities in China. With the aid of electrospray ionization-triple quadrupole mass spectrometry by setting precursor ion scans of m/z 35, m/z 81, and m/z 126.9, whole pictures of polar chlorinated, brominated, and iodinated DBPs in the tap water samples were revealed for the first time. Numerous polar halogenated DBPs were detected, including haloacetic acids, newly identified halogenated phenols, and many new/unknown halogenated compounds. Total organic chlorine, total organic bromine, and total organic iodine were also measured to indicate the total levels of all chlorinated, brominated, and iodinated DBPs in the tap water samples. The total organic chlorine concentrations ranged from 26.8 to 194.0 μg·L^–1 as Cl, with an average of 109.2 μg·L^–1 as Cl; the total organic bromine concentrations ranged from below detection limit to 113.3 μg·L^–1 as Br, with an average of 34.7 μg·L^–1 as Br; the total organic iodine concentrations ranged from below detection limit to 16.4 μg·L^–1 as I, with an average of 9.1 μg·L^–1 as I; the total organic halogen concentrations ranged from 31.3 to 220.4 μg·L^–1 as Cl, with an average of 127.2 μg·L^–1 as Cl.     

The occurrence of disinfection by‐products in Taiwan drinking water

In this study, samples were taken from six conventional water treatment plants for disinfection by‐products analysis. Results from the analysis revealed that trihalomethanes (THMs) concentrations in all samples were below regulatory levels (100 μg/L). Although the national standard for haloacetic acids (HAA5) has not yet been promulgated in Taiwan, samples from two water plants contained HAA5 concentrations exceeding the USEPA limit (MCL of HAA5 of Stage 1, 60 μg/L). THMs and HAA5 were found to be the major disinfection by‐products in all water treatment plants. It was noted that the concentration of HAA5 in most samples was higher than that of the trihalomathanes. However, the formation potential of THM (THMFP) was found to be higher than that of HAA (HAAFP). Good correlation also was found between THMFP (or THMFP) and HAA5 (or THMs). In evaluating the performance of the treatment processes, it was found that conventional water treatment processes followed by activated carbon were effective in removing disinfection by‐products (DBPs) from source water with pre‐ozonation. The treatment processes were at their optimum performance in removing contaminants when O₃/TOC₀ was held at 0.75.     

Assesment of disinfection by‐products removal by ozonation coupled with adsorption

This research work was performed to evaluate ozonation and granular activated carbon adsorption processes from the view‐point of controlling the formation of disinfection by products (DBPs). Both the humic acid and raw water were first preozonated and then adsorbed on the activated carbon to assess the potency for removal of total organic carbon (TOC) and DBPs. The disinfection by‐product including THMs and HAAs, in principle, can be successfully removed through a use of the ozonation and granular activated carbon (GAC) adsorption processes. However, in practice dealing with the raw water, it is necessary to introduce the pilot‐plant to obtain the design and operation guidelines for the water treatment plant through the ICA (Instrumentation Control and Automation) program in our future research work.     

Characteristics of carbonyls and volatile organic compounds (VOCs) in residences in Beijing,China

Volatile organic compounds (VOCs) and carbonyl compounds were measured both indoors and outdoors in 50 residences of Beijing in heating (December, 2011) and non-heating seasons (April/May, 2012). SUMMA canisters for VOCs and diffusive samplers for carbonyl compounds were deployed for 24 h at each site, and 94 compounds were quantified. Formaldehyde, acetone and acetaldehyde were the most abundant carbonyl compounds both indoors and outdoors with indoor median concentrations being 32.1, 21.7 and 15.3 μg·m⁻³, respectively. Ethane (17.6 μg·m⁻³), toluene (14.4 μg·m⁻³), propane (11.2 μg·m⁻³), ethene (8.40 μg·m⁻³), n-butane (6.87 μg·m⁻³), and benzene (5.95 μg·m⁻³) showed the high median concentrations in indoor air. Dichloromethane, p-dichlorobenzene (p-DCB) and toluene exhibited extremely high levels in some residences, which were related with a number of indoor emission sources. Moreover, isoprene, p-dichlorobenzene and carbonyls showed median indoor/outdoor (I/O) ratios larger than 3, indicating their indoor sources were prevailing. Chlorinated compounds like CFCs were mainly from outdoor sources for their I/O ratios being less than 1. In addition, indoor concentrations between two sampling seasons varied with different compounds. Carbonyl compounds and some chlorinated compounds had higher concentrations in the non-heating season, while alkanes, alkenes, aromatic compounds showed an increase in the heating season. Indoor concentration of VOCs and carbonyls were influenced by locations, interior decorations and indoor activities, however the specific sources for indoor VOCs and carbonyls could not be easily identified. The findings obtained in this study would significantly enhance our understandings on the prevalent and abundant species of VOCs as well as their concentrations and sources in Beijing residences.     

Evaluate HAA removal in biologically active carbon filters using the ICR database

The effects of biologically active carbon (BAC) filtration on haloacetic acid (HAA) levels in plant effluents and distribution systems were investigated using the United States Environmental Protection Agency’s Information Collection Rule (ICR) database. The results showed that average HAA5 concentrations in all locations were 20.4 μg·L^-1 and 29.6 μg·L^-1 in ICR plants with granular activated carbon (GAC) and ICR plants without GAC process, respectively. For plants without GAC, the highest HAA levels were observed in the quarters of April to June and July to September. However, for plants with GAC, the highest HAA levels were observed in the quarters of April to June and January to March. This HAA level profile inversely correlated well with water temperature, or biologic activity. For GAC plants, simulated distribution samples matched well with distribution system equivalent samples for Cl₃AA and THMs. For plants with and without GAC, simulated distribution samples overestimated readily biodegradable HAAs in distribution systems. The study indicated that through HAA biodegradation, GAC process plays an important role in lowering HAA levels in finished drinking water.     

Indoor and outdoor air PBDE levels in a Southwestern US city

Levels of polybrominated diphenyl ether (PBDE) flame retardants have been increasing in humans and the environment for the past few decades. Human levels are markedly higher in the US than Europe. Although food appears to be a significant route of intake, food PBDE levels are not substantially higher in the US than Europe. House and office dust appear to be major routes of exposure with air believed to usually provide a lesser route of intake. Because there are very few measurements of airborne PBDE that have been performed in relevant microenvironments in the US, increased efforts to assess airborne PBDE in the US as sources of exposure are needed. This study reports, for the first time from a Southwestern US city in Texas, the results of measurements of airborne PBDE in multiple locations, two outdoor and six indoor (residential and office) from active air sampling with collection of a combination of both vapor- and particulate-phase PBDE. Higher PBDE levels were measured in indoor than outdoor air, which confirms previous findings. Of 11 measured congeners including BDE 209, total PBDE levels in two outdoor air samples were 112 and 125 pg m^?3 and the indoor air levels ranged from 175 to 1232 pg m^?3 with a median of 572 pg m^?3. These findings suggest that sources of air contamination with PBDE may be similar in Texas as elsewhere in North America. However, more sampling is required to (1) better determine if this is the case and (2) attempt to characterize potential sources of PBDE contamination in both indoor and outdoor air by analysis of congener patterns.     

Control strategies for disinfection byproducts by ion exchange resin,nanofiltration and their sequential combination

● Effects of AER adsorption and NF on DBP precursors, DBPs, and TOX were examined. ● A treatment approach of resin adsorption followed by nanofiltration was developed. ● Both DOC and Br⁻ could be effectively removed by the sequential approach. ● DBPs, TOX, and cytotoxicity were significantly reduced by the sequential approach. Disinfection byproducts (DBPs) are emerging pollutants in drinking water with high health risks. Precursor reduction before disinfection is an effective strategy to control the formation of DBPs. In this study, three types of anion exchange resins (AERs) and two types of nanofiltration (NF) membranes were tested for their control effects on DBP precursors, DBPs, and total organic halogen (TOX). The results showed that, for AER adsorption, the removal efficiencies of DBP precursors, DBPs, and TOX increased with the increase of resin dose, and the strong basic macroporous anion exchange resin (M500MB) had the highest removal efficiencies. For NF, the highest removal efficiencies were achieved at an operating pressure of 4 bar, and the membrane (NF90) with a smaller molecular weight cut-off, had a better control efficiency. However, AER adsorption was inefficient in removing dissolved organic carbon (DOC); NF was inefficient in removing Br⁻ resulting in insufficient control of Br-DBPs. Accordingly, a sequential approach of AER (M500MB) adsorption followed by NF (NF90) was developed to enhance the control efficiency of DBPs. Compared with single AER adsorption and single NF, the sequential approach further increased the removal efficiencies of DOC by 19.4%–101.9%, coupled with the high Br⁻ removal efficiency of 92%, and thus improved the reduction of cyclic DBPs and TOX by 3.5%–4.9%, and 2.4%–8.4%, respectively; the sequential approach also reduced the cytotoxicity of the water sample by 66.4%.     

Indoor air quality in elementary schools of Lisbon in spring

Analysis of indoor air quality (IAQ) in schools usually reveals higher levels of pollutants than in outdoor environments. The aims of this study are to measure indoor and outdoor concentrations of NO₂, speciated volatile organic compounds (VOCs) and carbonyls at 14 elementary schools in Lisbon, Portugal. The investigation was carried out in May–June 2009. Three of the schools were selected to also measure comfort parameters, such as temperature and relative humidity, carbon dioxide (CO₂), carbon monoxide (CO), total VOCs, and bacterial and fungal colony-forming units per cubic metre. Indoor concentrations of CO₂ in the three main schools indicated inadequate classroom air exchange rates. The indoor/outdoor (I/O) NO₂ ratio ranged between 0.36 and 0.95. At the three main schools, the total bacterial and fungal colony-forming units (CFU) in both indoor and outdoor air were above the advised maximum value of 500 CFU/m³ defined by Portuguese legislation. The aromatic compounds benzene, toluene, ethylbenzene and xylenes, followed by ethers, alcohols and terpenes, were usually the most abundant classes of VOCs. In general, the indoor total VOC concentrations were markedly higher than those observed outdoors. At all locations, indoor aldehyde levels were higher than those observed outdoors, particularly for formaldehyde. The inadequate ventilation observed likely favours accumulation of pollutants with additional indoor sources.     

邻苯二甲酸二丁酯对拟南芥幼苗的氧化损伤（Oxidative Damage Induced by Dibutyl Phthalate to Stem and Leaves of Arabidopsis Seedlings）

为了探讨邻苯二甲酸二丁酯(DBP)对植物的氧化损伤作用,采用不同浓度的DBP溶液对拟南芥(Arabidopsis thaliana)进行染毒(终浓度为0、0.5、2.5、5、10mg·L-1),检测DBP对幼苗茎、叶超氧化物歧化酶(SOD)活性及丙二醛(MDA)含量的影响.结果表明:染毒1周后,随DBP浓度的升高,拟南芥幼苗茎叶MDA含量呈显著上升趋势,高浓度组(5、10mg·L-1)与对照组差异显著(p<0.01);SOD活性随DBP浓度的升高呈先升高后降低趋势,各染毒组与对照组均差异显著(p<0.01).以上结果表明DBP可对拟南芥幼苗产生明显的氧化损伤.     

Effect of treated swimming pool water on the levels of trihalomethanes in swimmer's urine

Swimming pools are considered to be the prime source for public exposure to trihalomethanes (THMs), mainly chloroform, because of their use for hygienic purposes. High doses of chlorine are easily perceptible by smell. The aim of this study was to measure simultaneously the THM levels in urine and blood of swimmers and in pool water itself (from city and university swimming pool), in order to investigate further the relationship between substances in different matrices at known environmental levels with uptake of these substances in indoor swimming pools. Volatile analytes were isolated and preconcentrated from the samples by thin layer headspace analysis (TLHS) with autogenous generation of the liquid sorbent. Chloroform, bromodichloromethane and dibromochloromethane were detected in the urine of all persons attending a swimming pool. Concentrations of THM compounds varied in the case of each swimmer. The research confirmed that approximately 10% of the volatile haloorganic compounds are excreted in urine in the unchanged form.     

广州夏季办公室内细颗粒中多环芳烃污染特征研究

大部分的都市办公人群每天在办公室至少度过8 h。而室外环境的渗透、办公室内吸烟、办公设备使用和中央通风系统均可能导致细颗粒物及多环芳烃(PAHs)在室内积聚而造成微环境污染。2015年5—6月,在广州市3种不同功能区(商住区、高新产业区、工业区)共选取了14间不同类型的办公室,对其室内外PM_(2.5)和多环芳烃进行同步监测。结果表明,(1)14间中有12间办公室内的PM_(2.5)浓度水平高于世界卫生组织(WHO)的推荐值25μg·m-3;(2)与国内外类似研究相比,办公室内外∑16PAHs及Ba P-eq的监测浓度水平均较低,并呈现一致规律:文印>室外>吸烟>多人>单人>无窗(无人),其中Ba P-eq低于欧盟规定的安全限值1 ng·m-3;(3)文印工作和吸烟行为与室内PM_(2.5)和PAHs浓度升高有密切关系,分别对5环和4环PAHs贡献明显;(4)其他无明显内源的办公室的细颗粒中PAHs污染在监测期间主要来源于室外贡献。     

黑土微生物量和酶活性对邻苯二甲酸二丁酯污染的响应

邻苯二甲酸二丁酯(di-n-butyl phthalate,DBP)是一种在环境中广泛存在的有毒有机化合物,已被我国列为优先控制污染物之一。本研究探讨了不同浓度的DBP污染对黑土呼吸、微生物量以及黑土酶活性的影响。结果表明,DBP污染处理的黑土呼吸速率和微生物量碳较对照均显著增加;微生物氮在DBP污染过程中呈"降低-升高-降低"波动性变化;微生物磷与DBP污染浓度呈显著负相关;DBP对黑土多酚氧化酶表现为先促进后抑制,对转化酶和蛋白酶活性表现为低浓度促进而高浓度抑制;在DBP污染过程中脲酶呈现被激活状态;黑土过氧化氢酶和酸性磷酸酶均受到DBP污染的显著抑制。通过相关性分析发现,土壤微生物量、土壤酶活性与DBP污染浓度之间存在着高度的相关性。由此可推断,DBP污染改变了黑土呼吸、微生物量和酶学活性的代谢特征,进而有可能影响了黑土的生态系统功能,威胁到黑土的可持续利用。