HJ 1111-2020Technical guidelines for eco-environmental health risk assessment - General principles (English PDF)

4.1 Evaluation principles

4.1.1 Scientificity

Fully collect existing data and information, based on the latest scientific evidence, according to the needs of ecological environment management, assessment purposes, and data availability and effectiveness, scientifically and reasonably determine the evaluation plan to ensure the systemicity and completeness of the evaluation process and the objectivity of the evaluation conclusion.

4.1.2 Hierarchical

Under the current awareness level and technical measures, according to the needs of ecological environment management, use the available data information and tools and methods, by from simple to complex, from conservative to practical, it is evaluated step by step.

4.1.3 Caution

The results of risk assessment should include the health of sensitive or highly exposed people exposed to chemical factors in the environment under the most unfavourable scenario in reality.

risk.

4.1.4 Transparency

The entire process of risk assessment should be fully and systematically recorded. Among them, special attention should be paid to the constraints, uncertain Contents and assumptions and their processing methods, different opinions and viewpoints in the assessment, and major decisions that directly affect the results of the risk assessment.

4.2 Technical guide system for ecological environment health risk assessment

The eco-environmental health risk assessment technical guide system is composed of general outline, basic method technical guide and application field technical guide.

The general outline stipulates the general principles, procedures, content, methods and technical requirements of ecological environment health risk assessment.

The basic method technical guide is a technical guide formulated for the general techniques and methods of each link of ecological environment health risk assessment.

A certain range can be used as the basis and basis for other guidelines.

Application field technical guidelines are special technical guidelines formulated for specific ecological environment management needs.

4.3 Evaluation procedure

The ecological environment health risk assessment procedure includes plan formulation, hazard identification, hazard characterization, exposure assessment and risk characterization. The assessment procedure is shown in Figure 1.

Hazard identification and hazard characterization together constitute a hazard assessment. The toxic effect and mode of action or mechanism determined by the hazard assessment are exposure assessment Provide a basis for the construction of exposure scenarios such as exposure pathways and exposure time. The exposure route, exposure time, exposure frequency and the exposure level and other information provide clues and basis for determining the key effect endpoints of the hazard assessment.

5.1 Clarify the purpose of evaluation

Before conducting a risk assessment, the risk assessor should fully communicate with risk managers and stakeholders, and clarify the ecological environment to be supported by the assessment.

Environmental management needs or ecological environmental issues that need attention.

5.2 Determine the scope of assessment

Determine the scope of assessment through data collection and analysis, personnel interviews, on-site investigations and ecological environment monitoring, including.

a) Target factors. Comprehensive consideration of source characteristics, environmental behavior, hazard characteristics and management requirements, etc., to determine the Chemical factors.

b) Time range. Comprehensive analysis of the hazard characteristics of the target environmental factors (such as acute or chronic), exposure time and duration, etc., Determine the time frame of the assessment.

c) Spatial scope. Comprehensively analyze the source characteristics, migration and transformation, exposure pathways and population distribution of the target environmental factors to determine the assessment the spatial extent.

d) Target group. According to the needs of ecological environment management, combined with the hazard characteristics of target environmental factors and the behavioral model of environmental exposure of people Types, population distribution, etc., clearly identify the population to be focused on.

5.3 Select assessment type

Types of risk assessment include qualitative assessment and quantitative assessment. According to the purpose of the evaluation, data availability, accuracy requirements, time Limit requirements, personnel and funding, etc., and select the appropriate evaluation type. Qualitative assessment usually uses descriptive words such as high, medium and low to indicate risk the size of. Quantitative assessment uses a numerical value to indicate the magnitude of the risk.

5.4 Determine the data acquisition method

According to the evaluation purpose and type of evaluation, methods such as literature, model prediction, experimental research or field survey are used to obtain the required data.

material. Existing data should be fully utilized in the assessment, and experimental research and field investigation should be carried out when necessary.

5.5 Clarify assessment content and requirements

Clarify the assessment content, methods, technical routes, quality control and the process of hazard identification, hazard characterization, exposure assessment and risk characterization.

Quality assurance measures to form an evaluation plan.

5.6 Determine the evaluation plan

Risk assessors should fully solicit opinions from risk managers and stakeholders, and determine the assessment plan after expert argumentation.

6.1 Evaluation content

Identify targets based on scientific data and literature information such as epidemiological investigations, in vivo tests, in vitro tests, and (quantitative) structure-activity relationships the toxic effects of environmental factors and their mode of action or mechanism.

6.3 Technical requirements

6.3.1 Data collection

A detailed literature search strategy should be developed to comprehensively and systematically collect the hazard identification or risk issued by domestic and foreign government departments or international organizations Evaluation report, toxicity data from domestic and foreign toxicity databases, published literature and toxicity test data, etc. For the collected literature or test Test data, delete duplicate data, eliminate irrelevant data, establish a database, and record in detail the process of document or test data screening.

The data types required for hazard identification include epidemiological survey data, in vivo test data, in vitro test data and (quantitative) structure-activity relationship Data etc. Specific data include.

a) Basic information, including chemical name, molecular formula, structural formula, molecular weight, etc.;

b) Physical and chemical properties, including density, melting point, boiling point, saturated vapor pressure and vapor density, solubility, chemical reaction of target environmental factors Application characteristics, stability, etc.;

c) Metabolism data, including the absorption, distribution, metabolism, excretion and accumulation of target environmental factors in humans and/or animals Metabolic kinetic data;

d) Toxicity data, including acute toxicity of target environmental factors, skin corrosion or irritation, serious eye damage or eye irritation, respiratory tract or Skin sensitization, germ cell mutagenicity, carcinogenicity, reproductive toxicity, specific target organ toxicity and inhalation hazard after one or repeated exposure Sex test data;

e) Epidemiological survey data, including environmental epidemiology and occupational epidemiology data, etc.;

f) Hazard level, including the acute toxicity, carcinogenicity, and reproductive toxicity of the target environmental factors.

6.3.2 Data quality evaluation

Develop a data quality evaluation plan to evaluate every aspect of research design, implementation process, quality control, data analysis, research results, etc.

The reliability of an epidemiological survey, in vivo test, in vitro test and (quantitative) structure-activity relationship literature or test data, and based on the evaluation results as a result, the reliability of literature or test data is classified as high, medium, low, or no information available.

At the same time assess the correlation between in vivo test, in vitro test or (quantitative) structure-activity relationship data and human toxicity, including the test substance to the target the representativeness of environmental factors, the rationality of test species selection, dose setting and end point selection, and the exposure route, method and time of exposure Relevance of exposure, etc.

The literature or test data with no available information and poor relevance is eliminated, and the process of quality evaluation of the literature or test data is recorded.

6.3.3 Evidence synthesis

Based on the literature or test data evaluated by data quality, identify possible health hazards or toxic effects of target environmental factors (such as acute toxicity) Sex, skin corrosion or irritation, serious eye damage or eye irritation, respiratory or skin sensitization, germ cell mutagenicity, carcinogenicity, reproductive toxicity Sexuality, neurotoxicity, immunotoxicity, developmental toxicity, etc.), effect endpoints (such as death, disease, changes in physiological functions or changes in biochemical metabolism Etc.) and possible modes or mechanisms of action.

For each possible hazard or toxic effect, classify and summarize its human evidence and animal evidence, and evaluate the possible heterogeneity of research results Evaluate and explain the evidence of the mechanism of action of health hazards or toxic effects, and display the results concisely in the form of graphs.

6.3.4 Evidence integration

Based on the comprehensive information of the evidence, for each possible health hazard or toxic effect, judge the evidence of human evidence and animal evidence separately it integrates information from different evidence chains such as human evidence, animal evidence, and mechanism evidence.

Make overall judgments about the causal relationship between health hazards or toxic effects (such as convincing evidence, probable evidence, possible evidence, According to insufficient data, etc.). For health hazards or toxic effects with convincing evidence or probable evidence, further hazard assessments will be carried out;

For insufficient evidence, it is necessary to confirm data gaps and decide whether to supplement survey, test or model data.

The content to be considered when judging the probative power of human evidence and animal evidence includes.

a) The reliability of human research or animal research itself;

b) The reproducibility of conclusions on the relationship between target environmental factors and health hazards or toxic effects among different studies, species or populations;

c) There is a dose-response (effect) relationship between the target environmental factor exposure dose, exposure time and health hazards or toxic effects;

d) The strength and accuracy of the correlation between target environmental factors and health hazards or toxic effects;

e) The relationship between the target environmental factor and the health hazard or toxic effect is consistent with the known biological principles;

f) The biological rationality of the toxic action mechanism.

When integrating human evidence, animal evidence, and evidence of mechanism of action, full consideration should be given to the repeatability of the evidence and the consistency between different types of evidence Consistency between related health effects, evidence from sensitive populations, and other supporting evidence, such as cross-reference prediction evidence.

7.1 Evaluation content

Based on hazard identification, qualitatively describe the hazard level of the target environmental factor causing the individual or group to have harmful effects; or establish the target environment the dose-response (effect) relationship between factor exposure and harmful effects, to derive toxicity parameters.

7.2 Evaluation steps

The hazard characterization assessment steps are shown in Figure 3.Generally follow the steps below.

a) Retrieve and evaluate the applicability of the conclusions on the hazards of target environmental factors issued by domestic and foreign government departments or international organizations. domestic If foreign government departments or international organizations have issued hazard characterization conclusions and applicable, they can be directly quoted; domestic and foreign government departments or international organizations have not published If the hazard characterization conclusion is issued, or the hazard characterization conclusion has been issued but is not applicable after evaluation, the risk assessor shall contact the risk manager and stakeholders Communication determines whether to continue the hazard characterization; after communication, if it is not necessary to continue, the hazard characterization will be terminated.

b) If the hazard characterization continues, determine the effect endpoint for the hazard characterization based on the hazard identification result and screen the relevant data.

c) Perform data quality evaluation on the hazard characterization data. If the requirements are met, the hazard level is divided, or the dose-response (effect (Should) model and derive toxicity parameters; if the requirements are not met and hazard characterization needs to be continued, test or survey data should be supplemented.

7.3 Technical requirements

7.3.1 Qualitative hazard characterization

The existing hazard classification results can be used directly, or according to the toxicity classification standards issued by domestic and foreign government departments or international organizations (such as chemical Product classification and labeling specifications), to classify the hazard levels of target environmental factors; or to establish a hazard level evaluation index system to determine Standard weight, construct hazard evaluation index, qualitatively or semi-quantitatively evaluate the hazard level of target environmental factors.

7.3.2 Quantitative hazard characterization

7.3.2.1 Data requirements and evaluation

The data required for hazard characterization includes epidemiological data, in vivo test data, in vitro test data and (quantitative) structure-activity relationship data.

Preference is given to using epidemiological data or in vivo test data. Hazard characterization data should meet the minimum data requirements stipulated by relevant national standards.

Data evaluation should follow the following principles.

a) When directly quoting the dose-response (effect) relationship function and toxicity parameters issued by domestic and foreign government departments or international organizations, it should be detailed Understand the key evidence, endpoints, starting points, assumptions, model methods, and determination of uncertainty coefficients on which these toxicity parameters are derived According to other information, and review the timeliness, reliability and applicability of the hazard characterization conclusions. When the conclusions of different institutions are inconsistent, the reasons should be analyzed, Carry out expert argumentation when necessary.

b) When deriving the dose-response (effect) relationship function and toxicity parameters based on the original literature data, the requirements of 6.3.2 shall be met, and the Quantitative measurement of exposure (or dose) and response, research design such as exposure (or dose) grouping, exposure (or dose) range and sample size it should be scientific and reasonable; when there are multiple data sources (such as population studies, animal studies, etc.), the advantages and disadvantages of different research types should be weighed.

7.3.2.2 Dose-response (effect) modeling

According to different exposure routes, exposure durations and toxic effects, determine the data and effects for dose-response (effect) relationship modeling According to the endpoint, establish the dose-response (effect) relationship function between the target environmental factor exposure and the effect endpoint. The general steps include.

a) When using in vivo test or in vitro test data to model the dose-response (effect) relationship, the kinetic model of toxicology metabolism is generally used.

Type or convert animal test doses into human equivalent doses through interspecies dose adjustment;

b) Determine the baseline response of the effect endpoint;

c) Do dose-response (effect) modeling for data within the range of observed exposure (or dose). Commonly used mathematical models include machine Physical models (such as one-strike model, multiple-strike model, multi-stage model, linear multi-stage model, random two-stage model, etc.) and probability Distribution model (such as probabilistic unit model, logistic model, Weibull model, etc.). Compare the goodness of fit of different models and select the best model Type, establish a dose-response (effect) function, and draw a dose-response (effect) curve.

7.3.2.3 Dose-response (effect) low-dose extrapolation

According to the needs of assessment, low-dose extrapolation is performed on the dose-response (effect) relationship of the unobserved exposure (or dose) range.

The general requirements for guiding toxicity parameters are as follows.

a) In view of the toxic effects of different exposure routes, exposure times and modes of action, respectively derive candidate toxicity parameters. Non-carcinogenic effects, the reference dose or reference concentration is generally derived; the carcinogenic effect is generally derived as the slope coefficient or unit risk factor for cancer.

b) For different toxic effects of the same exposure route and exposure time, select the most sensitive target organ toxicity parameter as the final toxicity parameter.

8.1 Evaluation content

Qualitatively or quantitatively estimate the external exposure of the population to the target environmental factors through different routes and pathways under a specific situation.

8.2 Evaluation steps

The assessment steps of exposure assessment are shown in Figure 4.Generally follow the steps below.

a) According to the purpose of the assessment, through scenario analysis or on-site investigation, determine the exposure scenarios of the population exposed to the target environmental factors;

b) Establish an exposure model based on the conditions and assumptions of the exposure scenario;

c) Determine exposure assessment methods for different paths and pathways, and qualitative exposure assessment needs to classify population exposure levels;

Exposure assessment needs to measure or predict the population's exposure concentration to target environmental factors, select population exposure parameters, and quantify the amount of exposure outside the population.

8.3 Technical requirements

8.3.1 Determine exposure scenarios

According to the purpose of the assessment, through scenario analysis and on-site investigation, determine the exposure scenarios of the population exposed to the target environmental factors. Including target ring Conditions and assumptions such as environmental factors and their sources, exposure pathways, exposure pathways, exposed population, exposure events, exposure time, exposure frequency, etc.

The rationality and completeness of the assumptions or conditions of the exposure scenario should be explained. The exposure scenarios should include the worst-case scenario assumptions. The exposed population should include Sensitive people and highly exposed people. When conditions permit, ambient air, soil, surface water, groundwater, indoor air, indoor dust, Information s...