Hazardous Substances

Risks and Regulations

Thomas Schupp

• Publisher: De Gruyter
• Year: 2020
• ISBN:
  9783110619799
• Edition: 1
• Topic: Physical Sciences
• Subtopic: Chemistry
• Index: Chemistry

This title presents a detailed overview on the full range of hazard categories and the associated risks of chemicals. It provides a basic introduction into toxicology, ecotoxicology and environmental behavior and enables all who perform precise chemical analysis to handle substances according to their intrinsic properties such as physical-chemical, environmental, ecological and toxicological hazards.

1 Introduction

Chemical engineers typically find employment in chemical industries and also in other industries where the knowledge about chemical reactions and chemical behavior and large-scale treatment of chemicals can be transformed into customer benefit. They are responsible for production, distribution and quality control of chemicals, for marketing and also for employees who handle chemicals.

Regulations in the European Union (EU) and in many other regions charge chemical engineers with responsibility for product safety, workplace safety, plant safety and regulatory compliance. As the text in the following chapters refers to EU legislation, a few words shall be dedicated to the basic meaning of the EU laws.

In the EU, legislative acts are enacted as “Regulation,” “Directive,” “Decision,” “Recommendation” or “Opinion”.¹ “Regulations” are directly and literally binding for the EU member states; member states have only that freedom for shaping the implementation that is explicitly granted by the regulation.

“Directives” are setting a certain framework and define common goals. Within this framework, the EU member states have some freedom how these “common denominators” are achieved and to be put into force. Member states are granted a certain time slot to integrate the directive into national laws.

A “Decision” addresses relevant parties directly; the addressed can be certain member states, companies, institutions or others. To those addressed, the decision is directly binding.

A “Recommendation” is an instrument to allow EU institutions to present their view on a kind of best or common practice for a “how to do,” without imposing any legal obligation to anybody.

An “Opinion” is a kind of an “expert judgement” of an EU institution; it is not legally binding.

EU Regulation is a legislation that is directly and literally binding to the EU member states. Freedom for national implementations is only possible as far as it is defined in the regulation.

EU Directives define common goals. After a certain time slot, EU member states have to implement the EU directive into national legislation.

Fig. 1: Simplified organigram of a company purchasing and producing chemicals. The lines indicate the company boundary. Expert departments may be incorporated in the company or bought-in as services. Occupational medicine is compulsory and may be part of the company or a service from a competent service provider. Products are supplied to other customers and/or directly to consumers. Safety instructions for customers have to be made available by the HSE department.

The flow of product and safety-relevant information is illustrated by the simplified organigram shown in Fig. 1. Together with the product purchased, safety-relevant information is provided to the Health, Safety and Environment (HSE) department. The consequences for plant safety and workplace safety are evaluated and supported by the occupational medicine and expert departments. These latter departments are also to be involved in the evaluation of own products. The expert departments may be part of the company, but services can be bought in by competent service providers. To involve expertise in occupational medicine is mandatory, and the involvement of expert departments is mandatory under certain circumstances, but always highly recommended for product liability reasons. For certain legal issues like export controls or high-liability applications (e.g., medicinal products, food contact materials), special legal advice might be necessary. Safety instructions are to be generated for the workers inside the company as well as for customers, workplace-related risk assessments and occupational hygiene measures, and the evaluation in terms of transport regulations (expert for dangerous goods) has to be organized by the HSE department. HSE is a “must have” in a company handling and dealing with dangerous substances, and chemical engineers may find employment in the HSE department. However, even if not employed in the HSE department, chemical engineers need to understand risks associated with chemicals to assure they neither do pose themselves, others or the environment to unacceptable risks nor run into product liability claims.

As a result, chemical engineers need to understand the behavior of hazardous substances, the associated risks and regulatory consequences. For that reason, lectures should be offered at least in master courses. For responsible management of chemicals associated risks, there is a need to understand basic principles of toxicology, ecotoxicology, environmental behavior as well as classification and labelling, regulations for the marketing of hazardous products and workplace safety. This textbook is intended as a guide accompanying students of chemical engineering through the respective areas of risks posed by chemicals and to provide the necessary background information.

In some parts, this textbook goes beyond the subjects needed to fulfill regulatory requirements. There are certain areas where chemical engineers should feel comparatively comfortable due to their education background. For example, toxicokinetics has many aspects in common with mass transfer in chemical reactors, and metabolism as well as environmental behavior can be matched against knowledge in reaction engineering. More in-depth information in these areas shall raise interest of chemical engineers in toxicology and ecotoxicology, enable them to actively participate in discussions with toxicologists and ecotoxicologists, and also make them ambassadors to the general public in discussing chemical risks on a rational basis.

Biology and physiology, on the contrary, are areas where students of chemical engineering are not familiar with. These subjects will be addressed on a limited scale, just sufficient to provide the necessary orientation in the area of risks posed by chemicals.

2 Physical and chemical properties of substances

Understanding physical and chemical properties of substances is a prerequisite for proper understanding of not only physical–chemical hazards, but also for the understanding of substance behavior in the environment and in organisms.

Environmental behavior covers the emission, distribution and fate of a substance in the environment, and this perspective shows similarities to the adsorption, distribution, metabolism and excretion (ADME) of a substance in an organism as discussed in Chapter 3, if an ecosystem (or nature) is regarded as an organism.

Physical–chemical properties of substances are part of their identification, and in the field of hazardous substances and risk assessment, proper identification and characterization is crucial for the success of toxicological and environmental investigations. This chapter starts with the identification of substances.

2.1 Identification of substances

Identification of a substance starts with simple physical properties that can be checked quickly and without sophisticated equipment. For solids, it is the melting point and visual appearance; for liquids, it is the refraction index, perhaps extended to boiling point, viscosity and density. These methods may provide a hint on purity, already, and it may occur that some limited data on identification are sufficient to check the specification of a product agreed upon between supplier and customer. Nevertheless, a more in-depth check on purity or identification of impurities can be very important. Just as one example: the substance aniline was the parent for the name “aniline-cancer,” describing bladder cancer that was comparatively frequently detectable in workforces in aniline production plants. Later, it turned out that impurities in the technical aniline – namely benzidine and 2-naphthylamine – were the causative agents. To detect and quantify such by-products and impurities, spectrometric and chromatographic methods are required. The European chemicals regulation actually requires the full characterization of a “mono-constituent” substance (see Chapter 8) submitted for registration by UV, IR, NMR and MS spectra, as far as appropriate, and to make use of chromatographic methods [gas chromatography (GC), high-performance liquid chromatography (HPLC) and thin-layer chromatography (TLC)] to identify every component that contributes to at least 0.1% to the technical substance. Lower detection limits may be required if the presence of specific critical impurities cannot be excluded.

2.1.1 Solid substances: melting point, granulometry, density

These are properties to characterize solids. Melting points are taken in melting point apparatus using capillaries, but also a heating plate equipped with a microscope may be use...

Table of contents

• Title Page
• Copyright
• Contents
• 1 Introduction
• 2 Physical and chemical properties of substances
• 3 Basics in toxicology
• 4 Basics in ecotoxicology and environmental behavior
• 5 Dose–response in toxicology and ecotoxicology
• 6 Classification, labeling and packaging of chemicals
• 7 A brief view on the classification and labeling of dangerous goods
• 8 Regulations concerning notification and marketing of substances in the European Union
• 9 Workplace safety
• 10 Storage of hazardous substances and mixtures
• 11 Properties of selected hazardous substances
• 12 Appendix 1: solutions to the exercises
• Index