石灰石和海泡石组配对水稻糙米重金属积累的影响

为了研究组配改良剂(石灰石+海泡石,LS)对于重金属Pb、Cd、Cu和Zn复合污染稻田的修复效果,在湘南某矿区附近稻田中进行了组配改良剂的田间试验。结果表明:施用0~1.8 kg m-2的组配改良剂LS使土壤pH和CEC显著增加,使土壤中Pb、Cd、Cu和Zn交换态含量显著降低。土壤Pb、Cd、Cu和Zn交换态含量的降低是pH升高,土壤胶体的CEC增加及土壤吸附能力增强的共同作用。施用组配改良剂LS显著降低了3个水稻品种(黄华占、丰优9号、Ⅱ优93)糙米中Pb、Cd和Cu的累积量,最大降幅分别为55.8%、66.9%、37.4%,而对糙米中Zn的含量没有明显影响。当LS施用量为1.8 kg m-2时,能使丰优9号糙米中Cd含量(0.195 mg kg-1)达到国家食品中污染物限量标准(0.20 mg kg-1)以下。土壤中交换态Pb、Cd和Cu含量的降低是糙米中重金属累积量减少的原因。土壤交换态Pb、Cd和Cu含量的对数值(lnC交换态)与其糙米中含量(lnC糙米)的对数值之间存在显著的线性相关关系。     

废料碳酸钙对低累积作物玉米吸收重金属的影响:田间实例研究

通过田间试验方法,研究了在铅锌矿废水污染的土壤上施用废料碳酸钙对第1、2季低累积玉米(Zea mays)产量以及重金属Cd、Pb、Zn和Cu含量的影响,并分析了施用废料碳酸钙后土壤pH和土壤有效态重金属含量的变化。结果表明,施用废料碳酸钙,玉米产量均有显著提高,其中高量废料碳酸钙处理效果最佳,第1季增产154%,第2季增产275%,玉米对Cd、Zn和Cu吸收量降低,玉米籽粒Cd、Zn和Cu含量降低到了国家食品卫生标准允许的含量水平。与对照比较,废料碳酸钙不同用量水平均能不同程度地提高土壤pH,降低土壤有效态重金属含量,并抑制茎叶Cd和Cu向玉米籽粒的转移,从而造成玉米籽粒重金属含量降低。     

湖南4个典型工矿区大豆种植土壤Pb Cd Zn污染调查与评价

通过对湖南4个典型工矿区（郴州柿竹园矿区、郴州宝山矿区、衡阳水口山矿区、株洲清水塘工业区）大豆以及其种植土壤的采样调查,综合评价了4个工矿区大豆及其种植土壤重金属污染程度。结果显示：（1）4个工矿区21个采样点的大豆及其种植土壤已经受到了重金属污染。土壤中Pb、Cd、Zn的浓度范围分别为269.02～6450.35、3.04～23.93、104.22～381.91mg·kg-1,大豆籽粒中这3种重金属的浓度范围分别为4.69～20.05、0.81～5.48、24.87～190.48mg·kg-1,均已超过相应的标准。（2）21个采样点中大豆植株对Pb、Cd和Zn的生物富集系数大小依次为Cd〉Zn〉Pb,表明大豆植株对Cd富集能力大于Zn和Pb。（3）21个土壤样品中交换态Pb、Cd、Zn含量与大豆植株样品各部位中这3种重金属元素含量基本上存在着显著或极显著的正的线性关系。     

2种含铁材料对水稻土中砷和重金属生物有效性的影响

通过盆栽试验研究添加2种含铁材料(Fe(OH)3、FeCl3)对污染水稻土壤中As、Pb、Cd、Cu、Zn生物有效性的影响。结果表明,添加Fe(OH)3对土壤As交换态含量没有显著的影响,添加FeCl3显著降低了土壤As交换态含量,添加量为0.50g/kg时,土壤As交换态含量比对照下降46%。添加Fe(OH)3使土壤Pb、Cu交换态含量显著降低,2.00g/kg的添加量使Pb、Cu交换态含量分别下降63%,74%。添加FeCl3使土壤Pb、Cd、Zn交换态含量显著升高,2.00g/kg的添加量使Pb、Cd、Zn交换态含量分别升高3 834%,247%,1 744%。添加Fe(OH)3对糙米中无机As和重金属Pb、Cd、Cu、Zn含量没有显著的影响,添加FeCl3显著降低了糙米中无机As含量,但显著提高了糙米中Pb、Cu含量,1.00g/kg的添加量使糙米中无机As含量降低33%,Pb、Cu含量分别升高147%,50%。表明添加FeCl3能有效降低土壤As的生物有效性,但提高了土壤重金属的生物有效性。添加Fe(OH)3对土壤pH无显著影响,而添加FeCl3能显著降低土壤pH值,这是FeCl3能有效固定土壤As,提高土壤重金属交换态含量的重要原因之一。     

组配改良剂对重金属污染土壤-蔬菜系统的修复效果研究

采用大田实验研究复合污染土壤中添加组配改良剂FQ12(沸石∶羟基磷灰石=1∶2)对受污染土壤和蔬菜中Pb、Cd、Cu、Zn 4种重金属的影响。结果表明,在添加FQ12后,土壤中重金属交换态含量大幅降低。辣椒可食部位中Pb、Cd、Cu、Zn含量也显著降低,FQ12添加量8.0g/kg时降低效果最好,Pb、Cd、Cu分别降低91.1%,58.3%,95.3%;Zn则是在4.0g/kg时,最大降幅达到89.4%,其他部位也有不同程度降低。在添加FQ12后,在一定程度上可以降低空心菜可食部位中Pb、Cd、Cu、Zn含量。在添加量为8.0g/kg时,4种重金属总量均达到最大降幅,最为明显的是Pb和Cu分别降低55.9%和50.7%,根部各重金属含量变化不大。由此可知,FQ12的施用对2种蔬菜吸收土壤重金属起到有效的抑制作用。     

连施石灰对 Cd污染土壤 Cd形态及稻麦吸收 Cd的影响

为探索成都平原轻度Cd污染耕地有效治理措施,以稻麦轮作耕地为研究对象,采用田间试验,施加不同梯度石灰作为钝化剂,研究连续3年施加石灰后,对土壤Cd形态以及水稻、小麦籽粒吸收Cd的影响。结果表明,当每季石灰施用量为2 250 kg/hm~2时,稻麦产量较高,籽粒重金属Cd含量达到《食品安全国家标准-食品中污染物限量》(GB 2762-2012)规定的限值。当石灰施用量为1 500～3 000 kg/hm~2时,能有效提高土壤pH值,改善土壤酸性。随石灰用量的增加土壤Cd有效性降低,且水稻、小麦籽粒Cd含量也随之降低。与对照相比,每季石灰施用量为2 250和3 000 kg/hm~2的处理,水稻籽粒Cd含量分别降低到0.12和0.08 mg/kg;小麦籽粒Cd含量分别降低到0.097和0.075 mg/kg。施用石灰可促进土壤中可交换态Cd向可还原态和残渣态Cd转换,土壤可交换态Cd从对照的44.1%降至3 000 kg/hm~2石灰处理的29.0%;而残渣态从对照处理的18.8%升高到34.3%。     

外源锌对水稻植株镉的累积差异分析

通过水稻威优46盆栽种植试验,研究了外源Zn施用(0,40,80,160 mg/kg 4个水平)对Cd中度(0.72mg/kg)和重度(5.26mg/kg)污染土壤中Cd生物有效性及水稻Cd累积的差异。结果表明:施Zn对各检测指标存在影响,但土壤Cd总量仍是土壤Cd活性和水稻Cd累积差异变动的主控因素。在Cd中度污染土壤中,施Zn降低了土壤交换态Cd含量1.9%~17.0%,但水稻根表铁膜、根和糙米中Cd含量随Zn施用浓度的增大而增大,糙米Cd含量从0.09mg/kg上升到0.17mg/kg,相关分析显示糙米Cd含量与土壤交换态Zn含量显著正线性相关。在Cd重度污染土壤中,施Zn增大了土壤交换态Cd含量2.1%~4.8%,但降低了水稻各部位中Cd含量,当施Zn浓度超过80mg/kg时,糙米Cd含量可从对照组的0.45mg/kg降低到0.12mg/kg,符合国家食品污染物限量标准(GB 2762-2017)的要求,相关分析显示糙米Cd含量与土壤交换态Zn含量显著负线性相关。对2种Cd污染程度的土壤,施Zn均可增大Cd在水稻地下部的累积率,从而降低水稻地上部Cd的累积率。在Cd重度污染土壤中,可通过施Zn降低糙米Cd含量,施Zn量80mg/kg是试验中最佳施用量;但在Cd中度污染土壤中,施Zn有增大糙米Cd含量的风险。     

硫磺对土壤Cd、Pb有效性的影响

采用盆栽试验,以无硫磺处理为对照,研究不同硫磺处理对土壤pH值、有效态Cd和Pb含量,以及对小油菜生物量、植株Cd和Pb含量的影响。结果表明,施用硫磺以后,土壤pH值在30d内明显降低,同时土壤有效态Cd、Pb含量显著升高。随着硫磺施用量的增加,土壤有效态Cd含量升高,不同处理之间差异达5%显著水平。30d时,160mmol/kg硫磺处理土壤有效态Cd含量为0.863mg/kg,比对照增加了1.98倍。小油菜干物质量随硫磺施用量的增加而增加,同时植株Cd含量也显著升高,植株地上部Cd含量最高可达491.35mg/kg,是同时期对照处理的1.64倍。植株吸收的Pb主要分布在地下部,说明试验中种植小油菜未能达到净化Pb污染土壤的目的。总之,施用硫磺具有强化小油菜对Cd的吸收,增强小油菜提取污染土壤Cd效率的功能。     

猪粪好氧堆肥对缺锌土壤种植大豆的影响研究

以Zn含量较高的猪粪为原料进行了90d好氧堆肥,以采自陕西省永寿县养马庄的典型缺锌土壤为供试土样,通过大豆盆栽试验研究了该有机肥对大豆生长的影响,并以污染指数评价法和地积累指数评价了施用该有机肥对土壤中重金属的累积环境风险。结果表明：经过90d的高温好氧堆制,获得了氮磷钾丰富的堆肥产品,且堆肥中未检测出Ni、Cd、Cr、Pb、Hg和As等有害重金属,仅含Cu256.3mg.kg-1、Zn474.4mg.kg-1。与对照相比,随着有机肥施用量的增加,大豆生物量和产量逐渐增加,并在肥土比10%时达到最高,大豆产量比对照提高了206.7%,大豆根系重量提高了94.2%,大豆茎叶（含荚壳）提高了94.0%;大豆籽粒中Zn含量则随着有机肥施用量的增加而逐渐增加,并在40%时籽粒Zn含量高达49.33mg.kg-1;施用堆肥后,土壤EC、Zn和Cu全量、Zn和Cu有效量均随着堆肥使用量的增加而增加,而土壤pH则随着堆肥比例的增加,从8.46逐渐降低到7.44。污染指数评价法和地积累指数评价法表明,当茬堆肥施用量不超过5%时,不会对该缺锌土壤造成重金属污染。研究显示,适量施用该堆肥能显著促进大豆的茎叶和根系生长,同时提高籽粒产量和籽粒中的Zn含量。对于供试缺锌土壤,施用该富锌有机肥可以明显补充土壤锌。     

施污土壤与污泥中Cu、Pb、Cd、Zn的形态分布

污泥中的重金属元素是限制其大规模农田利用的重要因素。施污土壤和污泥中重金属的形态研究可以用来评价土壤中重金属的生物有效性以及它们在土壤中的移动性。用修正BCR三步连续提取法进行分步提取研究了污水污泥和施污后的西红柿地土壤中Cu、Pb、Cd、Zn的形态分布状况。施用污泥堆肥10t hm-2后的土壤中Cu、Pb、Cd、Zn的全量与各种形态含量无明显增加,Cu、Pb、Zn含量远低于国家土壤环境质量标准。土壤中Cu的各种形态分布关系是:残渣态>可还原态=可氧化态>可交换态和弱酸溶解态,Cu在土壤中的存在是以最稳定的残渣态为主。堆肥污泥与干化污泥相比,残渣态Cu的比例明显增加。土壤中Pb的各种形态分布关系是以残渣态和可还原态为主,但可氧化态的分布比例最小。土壤中Cd的可交换态、可还原态和残渣态各占据相等的含量,但可氧化态Cd的含量几乎为零。Zn在土壤中的各种形态分布关系是:可交换态和弱酸溶解态>可氧化态>可还原态>残渣态,Zn在土壤中的存在是以最易迁移的可交换态和弱酸溶解态为主。这些金属元素在土壤中的相对稳定性顺序为:Cu>Pb>Cd>Zn。Zn在土壤中的移动性要远高于Cu。     

Bioavailability of As,Cd, Co,Cr, Cu,Hg, Mo,Ni, Pb,Se, and Zn from Biosolids Amended Compost

Appropriate compost standards are being considered in Canada. Five aspects of compost safety and quality are being evaluated; probably the most controversial aspect is the standards for metals in compost. In order to assist in the development of appropriate standards, the authors began an extensive research project in October, 1993 to determine the bioavailability of metals from compost and compost-metal mixtures. Swiss chard was grown in compost-amended soils or compost in a growth room using five treatments of increasing percentages of compost in the media (0, 25 percent, 50 percent, 75 percent, 100 percent compost (v/v)). A Truro loamy sand and a race-track manure-biosolids compost (RTM-biosolids) supplemented with a high metal biosolids were used in a completely randomized design with five replicates. Dry matter yield, metal content in plant tissue, and total metal uptake were evaluated as well as the total and DTPA-extractable metal content in the compost-soil mixes. The results of this and five other experiments conducted by the authors will help determine whether the suggested limits for As, Cd, Co, Cr, Cu, Hg, Mo, Ni, Pb, Se and Zn in composts are appropriate.     

Phytotoxicity of cobalt,vanadium, titanium,silver, and chromium

Abstract

The phytotoxicity of five nonessential elements (Co, V, Ti, Ag, Cr) to higher plants was studied in solution culture experiments with bush beans (Phaseolus vulgaris L. C.V. Improved Tendergreen). All, but in varying degrees, tended to concentrate in roots with a decreasing gradient to stems and leaves. Cobalt was one of the more mobile of the five trace metals. Its toxicity was expressed as severe chlorosis; 43 (with 10^‐5 M) and 142 (with 10^‐4 M) μg Co/g dry weight in leaves resulted in severe chlorosis. Vanadium as 10^‐4 M vanadate resulted in smaller plants but not in chlorosis. Leaf, stem, and root V, respectively, were 13, 8, and 881 μg/g dry weight. Titanium was somewhat mobile with considerable yield decrease at 10^‐4 M; leaf, stem, and root Ti concentrations, respectively, were 202, 48, and 2420 μg/g. Symptoms were chlorosis, necrotic spots on leaves, and stunting. Silver was very lethal at 10^‐4 M AgNO₃; at 10^‐5 M yields were greatly decreased, but plants were grown without symptoms. Leaf, stem, and root concentrations of Ag for this treatment, respectively, were 5.8, 5.1, and 1760 μg/g dry weight. Plants grown with 10^‐5 N Cr₂O₇ were decreased in yield by about 25% with or without EDTA (ethylenediamine tetraacetic acid) while the same level of Cr₂(SO₄)₃ was essentially without effect. For the two salts, the leaf, stem, root concentrations for Cr, respectively were 2.2 and 1.3, 0.7 and 0. 7, and 140 and 104 μg/g. Most of the trace metals studied here had interactions in the uptake and/or distribution of other elements.     

Variation of N,P, K,Ca, Mg,Mn, Zn,and al in slash pine foliage

Abstract

The seasonal patterns of foliage nutrient concentrations and contents were monitored for two growing seasons in an 11‐year—old Pinus el1iottii stand. In the first growing season after needle initiation, N, P, K, Mg, and Zn concentrations decreased, but this was followed by an increase in the fall and winter months. Another drop in concentration of all elements, except P, occurred in the second growing season. Decreases in total contents indicated that this drop was a result of translocation to other tissues. In contrast to the mobile elements, the concentration and fascicle contents of Ca, Mn, and Al increased with aging of the needles.

Between‐tree variability was least for N, P, and Zn and the N, K, Mg, Mn, and Zn in the current foliage had consistently lower variation than that in the 1‐year‐old foliage. Between‐tree variation for K was lower in the winter than the spring.

For pine foliage, recommended sampling period for N, P, Mg, and Zn is mid to late summer and for the other elements it is late fall to late winter.

There are several sources of variation that influence the level of nutrients in tree foliage. The most important of these, apart from the tree nutrient status, are seasonal fluctuations, variation between trees, and age of needles . Smaller sources of variation are associated with position of the needles within the crown, diurnal changes, year to year variation, and analytical errors^1,2. These variables must be studied in order to develop suitable sampling techniques and in Pinus this has been undertaken for P. banksiana ¹, P. taeda ³, P. strobus ⁴, P. resinosa ⁴, P. sylvestris ⁵, and P. radiata ^6,7. However, foliage sampling has not been studied in detail for slash pine (Pinus elliottii Englem var. elliottii) and earlier studies with other pines have been largely confined to temperate or cool climates.

This study reports the variation in elemental concentrations with season, age of foliage, and between slash pine trees growing in a subtropical climate in Florida.     

Cooking,Roasting, and Fermentation of Chickpeas,Lentils, Peas,and Soybeans for Fortification of Leavened Bread

The effects of cooking, roasting, and fermentation on the composition and protein properties of grain legumes and the characteristics of dough and bread incorporated with legume flours were determined to identify an appropriate pretreatment. Oligosaccharide content of legumes was reduced by 76.2–96.9% by fermentation, 44.0–64.0% by roasting, and 28.4–70.1% by cooking. Cooking and roasting decreased protein solubility but improved in vitro protein digestibility. Mixograph absorption of wheat and legume flour blends increased from 50–52% for raw legumes to 68–76, 62–64, and 74–80% for cooked, roasted, and fermented ones, respectively. Bread dough with cooked or roasted legume flour was less sticky than that with raw or fermented legume flour. Loaf volume of bread baked from wheat and raw or roasted legume flour blends with or without gluten addition was consistently highest for chickpeas, less for peas and lentils, and lowest for soybeans. Roasted legume flour exhibited more appealing aroma and greater loaf volume of bread than cooked legume flour, and it appears to be the most appropriate preprocessing method for incorporation into bread.     

Thin layer chromatographic determination of aflatoxins, ochratoxins, sterigmatocystin, zearalenone, citrinin, T-2 toxin, diacetoxyscirpenol, penicillic acid, patulin, and penitrem A.

A general method is described for determining 16 mycotoxins in mixed feeds and other food products used in the manufacture of these feedstuffs. The mycotoxins are extracted and cleaned up by extracting with solvents of different pH. Thin layer chromatography is used to separate the toxins; toxins are then quantitated by the limit detection method. The minimum detectable concentration of mycotoxins in various products is: aflatoxin B1 or G1, 4--5 micrograms/kg; ochratoxin A or ethyl ester A 140--145 micrograms/kg; citrinin 600--750 micrograms/kg; zearalenone, 410--500 micrograms/kg; sterigmatocystin, 140--145 micrograms/kg; diacetoxyscirpenol, 2400--2600 micrograms/kg; T-2 toxin, 800--950 micrograms/kg; patulin, 750--800 micrograms/kg; penitrem A 14,000--14,500 micrograms/kg; penicillic acid 3400--3650 micrograms/kg.     

Glucoraphanin and 4-hydroxyglucobrassicin contents in seeds of 59 cultivars of broccoli, raab, kohlrabi, radish, cauliflower, brussels sprouts, kale, and cabbage

The importance of dietary sulforaphane in helping maintain good health continues to gain support within the health-care community and awareness among U.S. consumers. In addition to the traditional avenue for obtaining sulforaphane, namely, the consumption of appropriate cruciferous vegetables, other consumer products containing added glucoraphanin, the natural precursor to sulforaphane, are now appearing in the United States. Crucifer seeds are a likely source for obtaining glucoraphanin, owing to a higher concentration of glucoraphanin and the relative ease of processing seeds as compared to vegetative parts. Seeds of several commonly consumed crucifers were analyzed not only for glucoraphanin but also for components that might have negative health implications, such as certain indole-containing glucosinolates and erucic acid-containing lipids. Glucoraphanin, 4-hydroxyglucobrassicin, other glucosinolates, and lipid erucic acid were quantified in seeds of 33 commercially available cultivars of broccoli, 4 cultivars each of kohlrabi, radish, cauliflower, Brussels sprouts, kale, and cabbage, and 2 cultivars of raab.     

Fluxes of Cu,Zn, Pb,Cd, Cr,and Ni in temperate forest ecosystems

The literature on the fluxes of six heavy metals in temperate forest ecosystems is reviewed. Special attention is given to wet and dry deposition and internal flux, to metal budgets for ecosystems and soils, to concentrations in aqueous compartments of the ecosystem and to speciation in soil solutions. Metal fluxes are discussed in relation to pollution load, soil type, tree species and land use. The mobility of Cu and Pb is strongly dependent on the solubility of organic matter. These metals are commonly accumulated in forest soils. Zinc, Cd and Ni are greatly influenced by soil acidity and are often lost in considerable amounts from acidified soils. Chromium is often at balance in forest ecosystems. Implications for metal solubility and budgets in forest soils are discussed in connection with an increase in soil acidification.     

Hydrophilic chromatographic determination of carnosine, anserine, balenine, creatine, and creatinine

A new HPLC procedure based on hydrophilic interaction chromatography (HILIC) has been developed for the simultaneous determination of carnosine, anserine, balenine, creatine, and creatinine in meat. This is the first time that HILIC has been directly applied to the study of meat components, having the advantage of not requiring complex cleanup and/or sample derivatization procedures. The chromatographic separation has been developed using a silica column (4.6 x 150 mm, 3 microm), and the proposed methodology is simple, reliable, and fast (<13 min per sample). The method has been validated in terms of linearity, repeatability, reproducibility, and recovery and represents an interesting alternative to methods currently in use for determining the mentioned compounds and other polar substances. The detection limits are 5.64, 8.23, 3.66, 3.99, and 0.06 microg/mL for carnosine, anserine, balenine, creatine, and creatinine, respectively.     

Volatilization of trifluralin,atrazine, metolachlor,chlorpyrifos, alpha-endosulfan,and beta-endosulfan from freshly tilled soil

The volatile and soil loss profiles of six agricultural pesticides were measured for 20 days following treatment to freshly tilled soil at the Beltsville Agricultural Research Center. The volatile fluxes were determined using the Theoretical Profile Shape (TPS) method. Polyurethane foam plugs were used to collect the gas-phase levels of the pesticides at the TPS-defined critical height above a treated field. Surface-soil (0-8 cm) samples were collected on each day of air sampling. The order of the volatile flux losses was trifluralin > alpha-endosulfan > chlorpyrifos > metolachlor > atrazine > beta-endosulfan. The magnitude of the losses ranged from 14.1% of nominal applied amounts of trifluralin to 2.5% of beta-endosulfan. The daily loss profiles were typical of those observed by others for volatile flux of pesticides from moist soil. Even though heavy rains occurred from the first to third day after treatment, the majority of the losses took place within 4 days of treatment, that is, 59% of the total applied atrazine and metolachlor and >78% of the other pesticides. Soil losses generally followed pseudo-first-order kinetics; however, leaching due to heavy rainfall caused significant errors in these results. The portion of soil losses that were accounted for by the volatile fluxes was ordered as follows: alpha-endosulfan, 34.5%; trifluralin, 26.5%; chlorpyrifos, 23.3%; beta-endosulfan, 14.5%; metolachlor, 12.4%; and atrazine, 7.5%.     

Evaluation of the cytotoxicity, genotoxicity, mutagenicity, and antimutagenicity of propolis from Tucuman, Argentina

This study evaluates the toxic, genotoxic/mutagenic, and antimutagenic effects of propolis extract from Amaicha del Valle, Tucumán, Argentina. The cytotoxicity assays carried out with the lethality test of Artemia salina revealed that the LD50 was around 100 microg/mL. Propolis extracts showed no toxicity to Salmonella typhimurium TA98 and TA100 strains and Allium cepa at concentrations that have antibiotic and antioxidant activities. Otherwise, for the testing doses, neither genotoxicity nor mutagenicity was found in any sample. The propolis extracts were able to inhibit the mutagenesis of isoquinoline (IQ) and 4-nitro o-phenylenediamine (NPD) with ID50 values of 40 and 20 microg/plate, respectively. From this result, the studied propolis may be inferred to contain some chemical compounds capable of inhibiting the mutagenicity of direct-acting and indirect-acting mutagens. A compound isolated from Amaicha del Valle propolis, 2',4'-dihydroxychalcone, showed cytotoxic activity (LC50 values of 0.5 microg/mL) but was not genotoxic or mutagenic. Furthermore, this compound was able to inhibit the mutagenicity of IQ (ID50 values of 1 microg/plate) but was unable to inhibit the mutagenicity of NPD. Our results suggest a potential anticarcinogenic activity of Amaicha del Valle propolis and the chalcone isolated from it.