土壤中铬的毒性阈值(ECx)及其预测模型

doi:10.13745/j.esf.sf.2023.11.55

摘要/Abstract

摘要：

毒物学资料的缺乏成为制约我国污染土壤中Cr生态风险评价及土壤环境质量标准修订的主要瓶颈。本研究选取了我国7种不同性质土壤,分别以蚯蚓生物量、小白菜生物量和微生物基质诱导呼吸(SIR)为毒性测试终点,基于Log-logistic剂量-效应关系及低剂量刺激效应函数模型对不同土壤中铬的毒性阈值(EC_x)进行了测定,在此基础上,对不同性质土壤中Cr的毒性阈值进行了预测。研究结果表明:不同性质土壤中Cr对蚯蚓、小白菜、土壤微生物毒性均随着土壤Cr含量的增加而表现出明显抑制效应,剂量-效应关系呈现明显的S型曲线;不同性质土壤中,基于微生物(SIR)、蚯蚓、小白菜毒性测试的EC₁₀分别为22.1~53.7、65.0~137.2和82.1~220.2 mg/kg,EC₅₀分别为50.3~103.7、103.9~369.0和159.9~441.9 mg/kg;不同物种Cr毒性阈值由大到小顺序为小白菜>蚯蚓>土壤微生物,土壤微生物对Cr毒性最为敏感;在土壤Cr低含量(<112 mg/kg)条件下,3种测试物种对Cr毒性表现出明显的低剂量刺激效应,其中,蚯蚓在不同性质土壤中最大刺激效应为102%~108%,小白菜为105%~112%,相对来说,土壤中Cr对微生物的低剂量刺激效应较小,最大刺激效应为104%;pH、黏土含量和土壤阳离子交换量(CEC)可以较好预测不同性质土壤中Cr的毒性阈值。研究结果对土壤中Cr的生态风险评价及土壤中Cr环境质量标准制、修订提供了科学依据。

关键词: 铬, 剂量-效应, 低剂量毒物刺激效应, 毒性阈值

Abstract:

The lack of toxicology data is the main factor hindering the ecological risk assessment of Cr contamination in soils and the revision of soil environmental quality standards in China. In this study, we conduct toxicology tests on seven soil types (with different soil properties) in China, using earthworm biomass, cabbage biomass, and microbial matrix induced respiration (SIR) as measurement endpoints. We determined the effective concentration (EC_x) values under different soil types based on the Log-logistic dose-effect relationship and low-dose stimulus effect function model. On this basis we developed predictive models for estimating toxicity thresholds of Cr under different soil properties. Chromium toxicity in earthworms, Chinese cabbage, and soil microorganisms under different soil types showed significant inhibitory effect with increased soil Cr concentrations, and the dose-response (D-R) relationship was clearly sigmoid in shape. Under different soil types, the EC₁₀ values for soil microorganisms (SIR), earthworms, and Chinese cabbage ranged between 22.1-53.7, 65.0-137.2, and 82.1-220.2 mg/kg, respectively, and the EC₅₀ values between 50.3-103.7, 103.9-369.0, and 159.9-441.9 mg/kg, respectively. The Cr toxicity thresholds for the tested species, from high to low, followed the order of Chinese cabbage>earthworms>soil microorganisms, with soil microorganisms being the most sensitive to Cr toxicity. Under low Cr concentrations (<112 mg/kg), the tested species showed significant hormesis effects, among which earthworms had a maximum hormesis between 102%-108% under different soil types, and Chinese cabbage between 105%-112%, while soil microorganisms showed relatively small effect at 104%. Chromium toxicity thresholds under different soil types can be well predicted based on soil pH and clay/CEC contents. The research results provide a scientific basis for the ecological risk assessment of Cr in soils and for the formulation and revision of environmental quality standards for Cr in soils.

Key words: chromium, dose-response, hormesis, toxicity threshold

中图分类号:

孙晓艺, 王萌, 秦璐瑶, 俞磊, 王静, 陈世宝. 土壤中铬的毒性阈值(EC_x)及其预测模型[J]. 地学前缘, 2024, 31(2): 121-129.

SUN Xiaoyi, WANG Meng, QIN Luyao, YU Lei, WANG Jing, CHEN Shibao. Toxicity thresholds (EC_x) for Cr in soils and prediction models[J]. Earth Science Frontiers, 2024, 31(2): 121-129.

图/表 6

表1 实验土壤性质

Table 1 Soil properties of the seven soil types tested

土壤地点		土壤类型	pH	土壤CEC/ (cmol·kg^-1)	OC含量/%	黏土含量/%	总Cr含量/ (mg·kg^-1)
海口(HK)	20°02'45.97″N, 110°11'38.39″E	砖红壤	4.93	8.75	1.51	23.00	48.21
桂林(GL)	25°27'35.66″N, 110°29'01.94″E	红壤	5.75	18.65	3.24	27.80	74.52
衡阳(HY)	26°89'32.31″N, 112°57'19.97″E	红壤	6.64	16.59	2.82	28.20	77.94
嘉兴(JX)	30°74'61.29″N, 120°75'54.86″E	水稻土	6.72	20.65	3.46	38.90	75.53
新乡(XX)	35°18'13.71″N, 113°55'15.05″E	潮土	7.30	12.82	1.05	15.80	61.38
保定(BD)	38°87'38.91″N, 115°46'48.15″E	潮土	8.15	9.52	1.21	20.63	54.59
德州(DZ)	37°16'53.14″N, 116°43'40.56″E	潮土	8.90	8.33	0.69	12.00	49.46

图1 土壤中铬毒性的剂量-效应关系拟合曲线

Fig.1 The dose-response curves of Cr based on various test endpoints in soils

表2 不同性质土壤中Cr的毒性阈值ECx

Table 2 Effective concentration (ECx, mg/kg) values of Cr under different soil types

土壤地点	蚯蚓
土壤地点	EC₁₀/(mg·kg^-1)	EC₅₀/(mg·kg^-1)	EC₁₀/(mg·kg^-1)	EC₅₀/(mg·kg^-1)	EC₁₀/(mg·kg^-1)	EC₅₀/(mg·kg^-1)
HK	65.0	103.9	82.1	159.9	22.1	50.3
	(39.2~71.5)	(88.5~119.5)	(50.1~96.3)	(149.2~171.3)	(11.8~34.8)	(38.0~62.7)
GL	85.9	187.9	126.6	261.2	42.0	74.9
	(52.8~133.9)	(168.1~209.9)	(72.0~195.5)	(216.1~315.6)	(20.3~68.3)	(60.2~102.4)
HY	109.2	171.5	133.3	294.3	47.0	83.0
	(78.0~152.8)	(150.6~207.4)	(79.0~199.9)	(245.8~352.5)	(22.0~79.1)	(63.5~127.1)
JX	107.1	259.3	173.8	321.8	53.7	92.4
	(70.5~187.1)	(225.4~298.3)	(95.8~223.5)	(270.9~382.3)	(36.9~78.1)	(72.3~117.0)
XX	85.1	253.3	105.0	302.4	36.0	81.2
	(48.0~124.6)	(159.7~281.2)	(67.0~143.3)	(175.5~333.4)	(25.0~51.8)	(67.8~97.2)
BD	137.2	369.0	220.2	441.9	42.7	103.7
	(65.8~193.5)	(345.8~496.0)	(81.4~277.4)	(203.7~487.3)	(25.3~72.1)	(65.5~122.8)
DZ	122.4	267.8	189.0	367.9	37.1	79.9
	(60.7~196.0)	(198.2~338.3)	(64.0~223.8)	(143.7~396.1)	(21.5~64.3)	(54.2~96.3)

图2 土壤中Cr对不同测试物种毒性阈值的比较 A—EC10;B—E C 5 0;C—不同试验终点的ECx分布特征。

Fig.2 Comparison of EC10 and EC50 values of Cr between different species under different soil types

表3 土壤中Cr对不同测试终点的低剂量毒物刺激效应

Table 3 Chromium(VI)-induced hormesis in different species under different soil types

土壤地点	蚯蚓			小白菜				SIR
土壤地点	Cr^*含量/(mg·kg^-1)	效应/%		Cr含量/(mg·kg^-1)		效应/%		Cr含量/(mg·kg^-1)		效应/%
HK
GL	102.4	104	105.2		105
HY	98.1	103	102.8		108		89.4		102
JX	98.7	108	99.6		112		87.6		104
XX			96.8		105
BD	106.3	102	95.9		106
DZ

表4 基于不同测试终点土壤Cr毒性阈值与土壤性质的回归关系

Table 4 Linear regression relationship between ECx values (Cr) and soil properties based on different toxicity endpoints

物种	回归方程	R²
蚯蚓	lgEC₁₀=0.924+0.358 lgpH+0.671 lgCEC	0.761^*
	lgE $C 1 0$ =1.013+0.717 lgpH+0.253 lgCEC+0.322 lg [w(OC)/%]	0.849^**
	lgEC₅₀=1.037+0.439 lgpH+0.747 lg [w(OC)/%]	0.702^*
	lgEC₅₀=1.161-0.934 lgpH+0.170 lgCEC+0.444 lg [w(OC)/%]	0.832^*
	lgEC₅₀=0.561+0.845 lgpH+0.342 lgCEC+0.086 lg [w(OC)/%]+0.420 lg [w(Clay)/%]	0.864^**
小白菜	lgE $C 1 0$ =1.132+0.357 lgpH+0.564 lgCEC	0.655^*
	lgE $C 1 0$ =1.235+0.767 lgpH+0.087 lgCEC+0.368 lg [w(OC)/%]	0.799^*
	lgEC₁₀=1.023+0.833 lgpH+0.833 lg [w(Clay)/%]+0.197 lg [w(OC)/%]	0.815^*
	lgEC₅₀=1.333+0.341 lgpH+0.670 lgCEC	0.615^*
	lgEC₅₀=1.474+0.905 lgpH+0.013 lgCEC+0.506 lg [w(OC)/%]	0.795^*
SIR	lgEC₁₀=0.489+1.120 lgpH+0.572 lg [w(OC)/%]	0.750^*
	lgE $C 1 0$ =-0.045+0.683 lgpH+0.694 lgCEC+0.010 lg [w(OC)/%]+0.191 lg [w(Clay)/%]	0.860^*
	lgEC₅₀=0.926+1.021 lgpH+0.533 lg [w(OC)/%]	0.726^*
	lgEC₅₀=0.461+0.579 lgpH+0.692 lgCEC+0.141 lg [w(Clay)/%]	0.853^**
	lgEC₅₀=0.668+0.628 lgpH+0.611 lgCEC+0.138 lg [w(OC)/%]	0.852^**

表4 基于不同测试终点土壤Cr毒性阈值与土壤性质的回归关系

Table 4 Linear regression relationship between ECx values (Cr) and soil properties based on different toxicity endpoints

物种	回归方程	R²
蚯蚓	lgEC₁₀=0.924+0.358 lgpH+0.671 lgCEC	0.761^*
	lgE $C 1 0$ =1.013+0.717 lgpH+0.253 lgCEC+0.322 lg [w(OC)/%]	0.849^**
	lgEC₅₀=1.037+0.439 lgpH+0.747 lg [w(OC)/%]	0.702^*
	lgEC₅₀=1.161-0.934 lgpH+0.170 lgCEC+0.444 lg [w(OC)/%]	0.832^*
	lgEC₅₀=0.561+0.845 lgpH+0.342 lgCEC+0.086 lg [w(OC)/%]+0.420 lg [w(Clay)/%]	0.864^**
小白菜	lgE $C 1 0$ =1.132+0.357 lgpH+0.564 lgCEC	0.655^*
	lgE $C 1 0$ =1.235+0.767 lgpH+0.087 lgCEC+0.368 lg [w(OC)/%]	0.799^*
	lgEC₁₀=1.023+0.833 lgpH+0.833 lg [w(Clay)/%]+0.197 lg [w(OC)/%]	0.815^*
	lgEC₅₀=1.333+0.341 lgpH+0.670 lgCEC	0.615^*
	lgEC₅₀=1.474+0.905 lgpH+0.013 lgCEC+0.506 lg [w(OC)/%]	0.795^*
SIR	lgEC₁₀=0.489+1.120 lgpH+0.572 lg [w(OC)/%]	0.750^*
	lgE $C 1 0$ =-0.045+0.683 lgpH+0.694 lgCEC+0.010 lg [w(OC)/%]+0.191 lg [w(Clay)/%]	0.860^*
	lgEC₅₀=0.926+1.021 lgpH+0.533 lg [w(OC)/%]	0.726^*
	lgEC₅₀=0.461+0.579 lgpH+0.692 lgCEC+0.141 lg [w(Clay)/%]	0.853^**
	lgEC₅₀=0.668+0.628 lgpH+0.611 lgCEC+0.138 lg [w(OC)/%]	0.852^**

参考文献 32

[1]	SINGH D, SHARMA N, SINGH C K, et al. Chromium (VI)-induced alterations in physio-chemical parameters, yield, and yield characteristics in two cultivars of mungbean (Vigna radiata L.)[J]. Frontiers in plant science, 2021, 12: 735129.
[2]	LARSEN K K, WIELANDT D, SCHILLER M, et al. Chromatographic speciation of Cr(III)-species, inter-species equilibrium isotope fractionation and improved chemical purification strategies for high-precision isotope analysis[J]. Journal of Chromatography A, 2016, 1443: 162-174.
[3]	DE FLORA S, BAGNASCO M, SERRA D, et al. Genotoxicity of chromium compounds. A review[J]. Mutation Research/Reviews in Genetic Toxicology, 1990, 238(2): 99-172.
[4]	ASHRAF A, BIBI I, NIAZI N K, et al. Chromium(VI) sorption efficiency of acid-activated banana peel over organo-montmorillonite in aqueous solutions[J]. International Journal of Phytoremediation, 2017, 19(7): 605-613.
[5]	SAHA R, NANDI R, SAHA B. Sources and toxicity of hexavalent chromium[J]. Journal of Coordination Chemistry, 2011, 64(10): 1782-1806.
[6]	SPEIR T W, KETTLES H A, PARSHOTAM A, et al. A simple kinetic approach to derive the ecological dose value, ED50, for the assessment of Cr(VI) toxicity to soil biological properties[J]. Soil Biology and Biochemistry, 1995, 27(6): 801-810.
[7]	鲁如坤. 土壤农业化学分析方法[M]. 北京: 中国农业科学技术出版社, 2000.
[8]	ZHANG X, ZHANG X, LI L, et al. The toxicity of hexavalent chromium to soil microbial processes concerning soil properties and aging time[J]. Environmental Research, 2022, 204: 111941.
[9]	HAANSTRA L, DOELMAN P, VOSHAAR J H O. The use of sigmoidal dose response curves in soil ecotoxicological research[J]. Plant and Soil, 1985, 84(2): 293-297.
[10]	李泽姣, 崔岩山, 蔡晓琳, 等. 土壤铬污染对赤子爱胜蚓抗氧化酶活性的影响[J]. 中国科学院大学学报, 2020, 37(1): 20-26.
[11]	王晓南, 刘征涛, 王婉华, 等. 重金属铬(Ⅵ)的生态毒性及其土壤环境基准[J]. 环境科学, 2014, 35(8): 3155-3161.
[12]	EZE M O, GEORGE S C, HOSE G C. Dose-response analysis of diesel fuel phytotoxicity on selected plant species[J]. Chemosphere, 2021, 263: 128382.
[13]	GILLER K E, WITTER E, MCGRATH S P. Heavy metals and soil microbes[J]. Soil Biology and Biochemistry, 2009, 41(10): 2031-2037.
[14]	OORTS K, BRONCKAERS H, SMOLDERS E. Discrepancy of the microbial response to elevated copper between freshly spiked and long-term contaminated soils[J]. Environmental Toxicology and Chemistry, 2006, 25(3): 845-853.
[15]	CHEN S, MENG W, LI S, et al. Overview on current criteria for heavy metals and its hint for the revision of soil environmental quality standards in China[J]. Journal of Integrative Agriculture, 2018, 17(4): 765-774.
[16]	AMIN H, ARAIN B A, AMIN F, et al. Phytotoxicity of chromium on germination, growth and biochemical attributes of Hibiscus esculentus L[J]. American Journal of Plant Sciences, 2013, 4(12): 2431-2439.
[17]	王爱云, 黄姗姗, 钟国锋, 等. 铬胁迫对3种草本植物生长及铬积累的影响[J]. 环境科学, 2012, 33(6): 2028-2037.
[18]	KUPERMAN R G, SICILIANO S D, RÖMBKE J, et al. Deriving site-specific soil clean-up values for metals and metalloids: rationale for including protection of soil microbial processes[J]. Integrated environmental assessment and management, 2014, 10(3): 388-400.
[19]	BERRY R III, LÓPEZ-MARTÍNEZ G. A dose of experimental hormesis: when mild stress protects and improves animal performance[J]. Comparative Biochemistry and Physiology Part A: Molecular and Integrative Physiology, 2020, 242: 110658.
[20]	BELZ R G, DUKE S O. Modelling biphasic hormetic dose responses to predict sub-NOAEL effects using plant biology as an example[J]. Current Opinion in Toxicology, 2022, 29: 36-42.
[21]	PATNAIK A R, ACHARY V M M, PANDA B B. Chromium (VI)-induced hormesis and genotoxicity are mediated through oxidative stress in root cells of Allium cepa L[J]. Plant Growth Regulation, 2013, 71: 157-170.
[22]	MORKUNAS I, WOŹNIAK A, MAI V C, et al. The role of heavy metals in plant response to biotic stress[J]. Molecules, 2018, 23(9): 2320.
[23]	UDDIN I, BANO A, MASOOD S. Chromium toxicity tolerance of Solanum nigrum L. and Parthenium hysterophorus L. plants with reference to ion pattern, antioxidation activity and root exudation[J]. Ecotoxicology and Environmental Safety, 2015, 113: 271-278.
[24]	TALEBI M, TABATABAEI B E S, AKBARZADEH H. Hyperaccumulation of Cu, Zn, Ni, and Cd in Azolla species inducing expression of methallothionein and phytochelatin synthase genes[J]. Chemosphere, 2019, 230: 488-497.
[25]	CALABRESE E J, AGATHOKLEOUS E, KOZUMBO W J, et al. Estimating the range of the maximum hormetic stimulatory response[J]. Environmental Research, 2019, 170: 337-343.
[26]	ZHANG X X, LIN Z F. Hormesis-induced gap between the guidelines and reality in ecological risk assessment[J]. Chemosphere, 2020, 243: 125348.
[27]	JARDINE P M, STEWART M A, BARNETT M O, et al. Influence of soil geochemical and physical properties on chromium(VI) sorption and bioaccessibility[J]. Environmental Science and Technology, 2013, 47(19): 11241-11248.
[28]	LIN X L, SUN Z J, ZHAO L, et al. Toxicity of exogenous hexavalent chromium to soil-dwelling springtail Folsomia candida in relation to soil properties and aging time[J]. Chemosphere, 2019, 224: 734-742.
[29]	LI B R, LIAO P, XIE L, et al. Reduced NOM triggered rapid Cr(VI) reduction and formation of NOM-Cr(III) colloids in anoxic environments[J]. Water Research, 2020, 181: 115923.
[30]	马虹, 王学东, 李金瓶, 等. 土壤理化性质对外源六价铬植物毒性的影响[J]. 生态毒理学报, 2021, 16(4)224-232.
[31]	ALYAZOURI A, JEWSBURY R, TAYIM H, et al. Uptake of chromium by Portulaca oleracea from soil: effects of organic content, pH, and sulphate concentration[J]. Applied and Environmental Soil Science, 2020, 2020: 1-10.
[32]	LOYAUX-LAWNICZAK S, LECOMTE P, EHRHARDT J J. Behavior of hexavalent chromium in a polluted groundwater: redox processes and immobilization in soils[J]. Environmental Science and Technology, 2001, 35(7): 1350-1357.