The History of Chemical Hazards

Historically, the first known toxins came from animals, plants and minerals. These toxins are naturally occurring and are still used commonly. Many professionals worked with chemical hazards in painting, mining and potting. The people most exposed to chemical hazards in early civilizations were miners, mineral processers and potters. These occupations were most dangerous due to the lack of knowledge about toxins such as lead, mercury and radon. Throughout history, chemical hazards were addressed, but it took a long time. In prehistory toxic substances were not well explored. Considering the life expectancy at the time, chemical hazards were also not the main concern for survival. With that being said, humans have been studying toxins for thousands of years. The study of toxins dates to as early as 1500 BC where Papyrus Ebers, an important king from Egypt, had prescriptions of toxic plants and metals such as lead, copper and antimony. His collections were likely medicinal which shows that different civilizations could’ve had a grasp on toxicology. This is evidence that humans could’ve been aware of the positive and negative effects of toxins. In the 1800s industrialization created many hazards while trying to find solutions for painting, dyes, mining and pesticides. These hazards were not regulated both because of ignorance and corporate negligence. Once these chemical solutions were discovered, corporations were not interested in their negative effects.

In this chapter, I will explore the development of risk management and the growing concerns around chemical hazards in the past 200 years. I will expand on the four different eras of toxicology following the introduction of industrialization in the 1800s. Many jobs were created as science progressed. The science around chemicals progressed much faster than the safety concerns which led to countless disasters and large exposures. These exposures helped to create and implement global legislation and regulations. Unfortunately, it took until the 1970s to address these issues politically.

Due to the lack of research before the 20th century, many workers were likely unaware of the negative effects of exposure to toxins. There are also many cases in which the workers were unaware, but the bosses were and risked the workers knowingly. Corporate negligence is a trend in the past 200 years that highlights the classist nature of toxic substances. Some of this included slave labor, largely in the Roman empire, but also America. Mining for materials such as mercury was delegated to slaves. In Spain, this dates to as early as 400BC, when they used slave labor to not expose themselves. The need for mercury outweighed the concerns of it’’s chemical exposures. This shows that the Spaniards were likely aware of the risks associated with mercury exposures and made others do that work. This is not a single instance, it is a trend. Racism and classism have played a large role in the exposure to chemical hazards. Work such as coal mining has been primarily done by poor, working class people. This work is extremely dangerous because of the dust particles from coal. The division of labor is inherently racist, and chemical exposures are a prime example of this. With class structure being more defined, workers were pushed into boxes and given few choices for work. In ‘Chemical Hazards in Workplaces, Prehistory to the Present’, Ulf Ulfvarson explains: “Wage conflicts gave rise to coercion acts as counter measures. This development contributed to a concentration and intensification of the exposure to chemical health risks at work.” This quote shows that the intentions of the people in power were not accidental. Slave labor was used until it was outlawed, which led to the lower class filling the gap. Workers such as coal miners are tied down to dangerous jobs with little or no alternatives. With more division in class structure, chemical hazards have become a more prevalent environmental justice issue.

America is built on the back on slavery and that cannot be understated. Slaves were forced to do most of the agricultural work. Plants such as tobacco contain toxic chemicals like nicotine. Nicotine is dangerous because you can become sick from exposure. Nicotine sickness looks like the flu with throwing up being a common symptom. The absorption of nicotine is usually through the skin. Children in modern day America have also consistently done this farm work.

Another modern example of marginalized groups forced into dangerous work is the radium girls who were female factory workers. They painted watch dials with radium and would often lick their paintbrushes to clean them. They were encouraged to do so. Many of these women experienced radium poisoning. The woman were chosen for the job because of their small hands, which could paint inside the watch dials. This example shows a lack of education around the toxin. Most of these women passed away, and the ones that survived were seriously hindered. They were known to look radioactive, as their teeth and skin would glow from all the radiation. As research has progressed, most modern exposures are predictable, and the workers put at risk are knowingly put in harm’s way.

Risk management for chemical hazards has changed drastically over the past 100 years with legislation including the clean air act and the clean water act. These regulations have improved the air and water quality in the environment. Unfortunately, less has been done to limit hazards in the workplace. Certain professions such as mining and chemical plant workers are still dealing with exposure to hazards. As mentioned earlier, many of these workers do not have opportunities for different work. They are often poor, marginalized people.

Some of the most toxic chemicals include arsenic, lead and mercury. Historically, lead has been in many modern-day items such as gasoline and paint. The CAA restricted leaded gasoline, and it was phased out in 1996. Before that, fumes were put out into our atmosphere and exposure led to reduced IQ, neurological and behavioral issues. These exposures were widespread and common because most, if not everybody was around leaded paint or gasoline. Some were more affected than others due to previous conditions. Children and the elderly are at an increased risk because they are more likely to be exposed. This can happen because children may ingest lead paint and elderly people have less autonomy over their exposures. Lead paint was used up until 1978 and many buildings are still coated in it to this day.

Another important piece of legislation is the Toxic Substances Control Act of 1976 (TSCA). This was the beginning of chemical hazards in the workplace being addressed seriously. It demands companies educate their workers about the dangers and potential risks of the hazards they could be exposed to. This legislation led to a national movement called the Hazardous Communication Standard or HCS. This was a set of guidelines created by OSHA to expand on the TSCA. It made employers educate workers, like the TSCA but also added regulations to make workplaces consistently safer. The Globally Harmonized System is a global expansion of the Hazardous Communication Standard to make sure no workplaces are left behind. This was implemented in 1992 and much work was done between 1992-98, but it is still around today. While it is evident that chemical hazards have been addressed, the historical patterns of racism and classism persist. Regardless of if workers are educated, many do not have an occupational choice. This means they are forced to do work that is dangerous. Even though workers are now often educated, the issues that affect marginalized groups have continued at a disproportionate rate. While there is growing awareness about these issues it has not been politicitzed. This is likely do to the people in power benefiting from this power dynamic. Cheap, dangerous work has been a key role in building American infrastructure, and that is not likely to change any time soon.

Throughout modern history, toxicology has been split into four different groups. The first being normalization. This period in time descibes the rapid growth of industrialization and the creation of many dangerous jobs. New chemical hazards were being created, and many factory workers were put in harm’s way. This was normalized and not addressed, hence the name normalization.

The second period is called fixing toxicology where concerns about chemical hazards were raised. Instead of trying to limit exposures, they tried to stop them all together. This is not attainable because civilization was not willing to stop producing the goods that caused the chemical hazards. This period led to people setting ‘safe’ boundaries for hazards. We know that for many chemicals, any exposure can be dangerous. Attempts to put safe boundaries on toxic substances were not successful and many workers died or were seriously injured.

The third period is considered toxic environments. In the post-world war two era research concluded that you could not set safe boundaries on toxicology, and the scientific world came together to better understand toxic substances. This era defines much of our current knowledge of toxins such as mercury and arsenic.

The fourth and final period of toxicology refers to the 1970s where these concerns became global, and toxicology was politicized also known as the environmental movement. This is in line with legislation such as the CWA, CAA and the TSCA. Very quickly, regulations were put in place to stop workers from being seriously hurt from exposure. Limiting exposure altogether became a much more popular idea. Unfortunately, disasters and large exposures around chemical hazards played a big role in spurring this movement forward.

Lead, mercury and arsenic are the most toxic metals we know of. The current list of the top ten most hazardous has changed over time. Currently the top 10 are Arsenic, lead, mercury, vinyl chloride, polychlorinated biphenyl (PCBs), benzene, cadmium, benzo(a)pyrene, polycyclic aromatic hyrdocarbons (PAHs) and benzo(b)fluoranthene. This rating is from 2007 which is the most updated version of this list. Arsenic has been used in wood preserving, alloying metals, processesing glass, paper and metal adhesives.

Over the years arsenic has been found to be more toxic than previously imagined. Although it is more toxic than previously imagined, it has always been known to be deadly. The romans often used it to execute criminals or people who offended the kings. Albertus Magnus is widely considered to have discovered the metalloid in 1250. It was commonly used as a poison for many reasons. It is easily found in nature and has an odorless taste. There is a long history, specifically in Italy of arsenic poisoning which led to the death of many kings, queens and royal families. Natural death for royalty was considered to be non-existent. With the knowledge of anatomy, testing for poisons in the body became more prevalent and it was essentially phased out as an assassination tool. This is because the assassins were able to be caught now that the poisonings could be proven.

Paracelsus is a well-known figure in toxicology, often declared the father of toxicology. He decided to study medicine at a young age and discovered that chemical substances could also be used medicinally. Although we have a much more distinguished dose-response rate now, he was aware of it back in the 16th century. He traveled across Europe, learning at many different universities. He studies workers who were exposed to toxins and mainly focused on medicines to heal wounds. He was rebellious in his field and rejected the common ideas of Galen and Avicenna to provide a better understanding of the benefits of chemicals medically. Before his studies, many chemicals such as copper were just seen as toxic but he discovered that they could be used positively in smaller doses.

Another important figure in the history of chemical hazards is Bernardino Ramanzzini, who is considered the father of occupational medicine. He compiled previous information on workers and their hazards. He wrote a book about the common diseases workers developed and why they did. He normalized asking patients what they do for work to better understand why they’re experiencing the symptoms they are. He also believed that not all working diseases were caused by chemicals, but instead prolonged positions that could cause physical stress.

Alice Hamilton is another important figure in the world of toxicology and workplace exposures. Much of her research was to improve the working conditions for poor, inner city people. This is essential because as I’ve mentioned, these people are often left behind. She worked as a bacteriologist at Chicago’s memorial institute for infectious diseases. There, she combatted issues facing workers and advocated for their rights. In the early 20th century, there was no legislation and little regulation to protect workers. She discovered that many factory workers were dealing with chemicals that were deadly to them. She specifically worked on the research of white lead and lead oxide. She found that paint workers were exposed and ingested lead at a dangerous rate. This also helped the rest of the world understand that lead is very toxic. As we know, it was still commonly used up until the 1990s, but her research helped to pave the way for its eradication. She was able to recommend safer working conditions and how to address these chemicals when it came to the general public. There was no concern at the time for the effects on children. Her work advanced the study of public health in general. She was an advocate for the working class and played an essential role in addressing the disproportionate effects of toxic substances on the working class and people of color. She also helped the government focus on aniline dyes, carbon monoxide, mercury, tetraethyl lead, benzene and hydrogen sulfide gases. Due to the nature of her rebellious actions, she was closely followed by the FBI. This is essential to understand that the government was not always keen on her scientific advancements. She pushed the people in power to address issues facing the less privileged,which helped to dismantle systems of oppression.

Rachel Carson is also an essential figure in addressing the specific pesticide, DDT. Her book, Silent Spring helped inspire the environmental movement of the 1970s. She wrote about how the chemical used as an agricultural pesticide was killing animals that were not the intended target and also affecting human health. The idea of silent spring is that the birds were no longer there to chirp and make noise. Her moving book helped to educate the public and raise awareness to the negative side effects of important things like pesticides. Her writing coincides with legislation in the 70s. The environmental movement was a large political act to address concerns to the environement but it is very relevant to chemical hazards. The main concerns were with fossil fuels and how they would affect the planet, but concerns rise for the workers who had to deal with them. Coal mining has been a prevalent part of fueling the modern world and specifically America in the 1800s to now. Coal mining is dangerous because it is easy for the coal particles to build up in your lungs. Absorbtion comes from respiratory and skin contact. Workers often develop a disease called black lung. The dust particles from coal break off and build up and it can take years for the buildup to go away. It can cause trouble breathing, shortness of breath and leave lasting impacts. Workers were aware that their occupation was the reason for their struggles but often times did not have other oppurtunities for work. This is specifically common in Appalachia, where much of the coal mining in America is done. This region is poor and workers will do anything to make money for their family including risking their health. While we have known this, corporate negligence made it hard to address. Coal was seen as a necessary fuel and alternatives were not common until recently.

A lot of awareness around chemical hazards has unfortunately been from tragedies such as the Bhopal gas disaster and Chernobyl. The Bhopal gas tragedy happened in 1986 when a leak from a pesticide plant exposed 500,000 people to the very toxic chemical methyl isocyanate. Bhopal India is a densely populated city so many people were in the vicinityof the spill. Before, global regulations were very slim so America and other 1st world countries would outsource their work. The company Union Carbide India Limited was majority owned by the Union Carbide Corporation. This corporation was based in America. While the developed countries became aware of issues associated with pesticides, they knew they could work around regulations by moving work to the developing world. In 1992 the Global Harmonized System began to address this issue.

Overall the development of the modern world created many substances deemed necessary for industries such as mining, agriculture, painting and preservation. These industries have developed quickly scientifically, but the culture was generally unaware of the risks. A prime example of this is lead. After industrialization, slave labor was used to avoid harm for the people in power. Following the end of slavery, cheap labor was used to force the working class into dangerous jobs. Research around chemical hazards were limited until the 1900s when Alice Hamilton helped to pave the way for toxicology. Her ideas were unpopular because they challenged the power dynamics that forced working class people into dangerous work. While her ideas did not catch on right away, they helped pave the way for the environmental movement which included legislation such as the CWA, CAA and the TSCA. Toxic substances have continued to be an issue of classism and racism. America was built on slavery and at the time of its end, the people in power created a division of labor to force working class people into dangerous work. It was in their best interest to not address chemical hazard exposures because the work was considered important. Not until after world war 2, did these issues become politicized. The environmental movement in America forced corporations to outsource work to the developing world in another attempt to not address these hazards. Several catastrophic events such as the Bhopal gas tragedy began the GHS, or Global Harmonized System. This system made regulations and bodies like OSHA into a global network so there could be no outsourcing. Companies have continued to cut corners when it comes to safety but regulations and education around chemical hazards is much better than it has been. Over the past 200 years we have gone thru four stages of toxicology commonly referred to as normalization, fixing toxicology, toxic environments and fragmentation. Normalization explains the period of industrialization, fixing toxicoligy is the era in which people in power tried to put safe guidelines on toxins. Toxic environments is the post-world war 2 era where civilization realized you could not fix toxicology, and the hazards have no safe levels. Fragmentation is the period of politization, and the environmental movement inspired largely by Rachel Carson. Now, chemical hazards are seen as an important part of public health and addressing them both in the workplace and the environment is popular.

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Class slides: Occupational Health