BPA - Why Our Plastic Bottles Need to Be BPA free?

(image taken from Clean Body Living website)

We often notice this sign saying 'BPA free' when we walk down the aisles of hypermarket displaying various types of plastic drinking bottles. It seems like a must for the prestigious plastic bottle manufacturers today to put the sign on their products so that customers will be like 'oh ok, BPA must be something nasty, since it says it is free from this substance, it must be safe to use', without actually knowing what BPA is.

Back to 1891...

BPA stands for bisphenol A, a chemical substances that is used in manufacturing of polycarbonate plastic (PC) derived from petroleum. It was first synthesized as early as 1891 by a Russian chemist named Aleksandr Dianin (but it was first mentioned in scientific paper in 1905 by Thomas Zincke from Germany, and of course it was written in German that I couldn't understand the content). Only after over 60 years, in 1953, two scientists - Dr. Hermann Schnell and Dr. Daniel Fox - respectively discovered PC through the reaction between BPA and phosgene. Both of them were amazed by its durability and strength, and continued developing this polymer. At the beginning, this material was used in electrical and electronic appliances and then slowly moved into industries producing plastic bottle and lining of canned food.

Introduction to Emerging Contaminants (ECs)

(Image taken from Clean Water Action website)

Water is one of the most vital components in human life that 3.4 millions people die each year due to water-related diseases, which is more than the lives claimed in wars. During the 19th century, one of the water-borne diseases named Cholera spread from Ganges delta in India throughout the world that it created another 6 subsequent pandemics which killed millions of people from all continents. Around 430 - 424 B.C.E., it is believed that Typhoid fever wiped out one third of the population of Athens, bringing the Golden Age of Pericles to an end. Besides the diseases related to water contaminated by bacteria, mosquito-borne diseases such as Malaria and Dengue which are discovered since 2700 B.C.E. and 265 C.E. respectively are also closely-related to our water since mosquitoes require stagnant water to breed. At around 20th century, contamination of water by heavy metals such as lead and mercury is being taken seriously since after the incidents of lead and mercury poisonings.

Silent Spring - Extracted Information (The Elixirs of Death) & Bioaccumulation

[Disclaimer: The information below is taken from the book 'Silent Spring' written by Rachel Carson with some online researches. If there is any misleading information please let me know.]

Bioaccumulation
Before we get into this chapter of Silent Spring, we should be clear about why organic insecticides are so sinister - They can bioaccumulate in our body.

1) When you accidentally take in those chemical (swallowed / absorbed through skin / inhaled) no matter how small the amount is, they will be stored up in your body fat because they are fat-soluble.

2)The chemical will be piled up in your body fat little by little until it reaches a concentration which can make you ill or even dead. So there is no 'safe' amount that you can consume.

3) The chemical can be transferred down the food chains. When a cow eats hay contaminated with organic pesticides, the chemicals will be stored in their fat and also milk. Then the milk is made into butter which will contain much higher amount of chemical.

4) It is proven that organic pesticide can be transferred to infant through milk and placenta, exposing the threat to children who are more susceptible to poisoning.

Various products of pesticides.
(Image taken from Environmental Health Matters Blog)

Chapter 3: The Elixirs of Death

INORGANIC PESTICIDE

Arsenic

• found naturally in ores of various metals, small amount in volcanoes, sea water and spring water
• found in English chimney soot
• tasteless, been used in homicide for a long history
• carcinogenic (cancer-causing)
• used as herbicides in 1951 (usually in sodium arsenate form) due to shortage of sulphuric acid to burn off potato vines

- The usage of arsenic at cotton plantation of southern United States nearly wiped out bee-keeping industry
- many livestock and wild animals die, water became unfit to be consumed
- in 1959,one of the major English chemical companies stopped the production of arsenical sprays after the death of a farmer's wife who drank contaminated water
- in 1961, Australia government announced a ban on arsenical herbicides but there was no restriction in United States

ORGANIC PESTICIDES - chlorinated hydrocarbons

Examples of chlorinated hydrocarbon pesticides.
(Image taken from NC State University website)

Dichloro-diphenyl-trichloro-ethane (DDT)

• created by German chemist in 1874, used as pesticide in 1939 by Paul Müller from Switzerland (Nobel Prize winner) to fight insect-borne diseases and crop destroyers
• harmless in powder form, used to combat lice during wars
• 3 ppm can inhibit essential enzyme in heart muscle
• 5 ppm can cause death in liver cells

- individuals with no known exposure can have 5.3 to 7.4 ppm in body

- agricultural workers can have up to 17.1 ppm

- workers in pesticide industry can have up to 648 ppm

Chlordane

• a diet of 2.5 ppm can be accumulated up to 75 ppm in fat

- 25% industrial solution spilled on skin caused poisoning symptoms in 40 minutes and death

Heptachlor

• constituents of chlordane
• converted into heptachlor epoxide in soil and living organisms
• 4 times as toxic as chlordane

Chlorinated naphthalenes

• causes hepatitis
• causes fatal disease in cattle
• threatening workers in electrical industry and agriculture

Dieldrin

• 5 times as toxic as DDT when swallowed, 40 times as toxic when absorbed through skin
• affect nervous system, causing convulsion
• causes severe damage to liver

Aldrin

• will be converted into dieldrin
• causes degenerative change to liver and kidney
• causes sterility
• a size of aspirin tablet can kill 400 quail

Endrin

• 5 times as toxic as dieldrin

- a baby contacted endrin residue lost sight and hearing and had muscular spasms

ORGANIC PESTICIDES - alkyl / organic phosphates (organic esters of phosphoric acid)

Structure of some organic phosphate pesticides.
(Image taken from Openi website)

Parathion

• discovered by German chemist, Gerhard Schrader in late 1930's as weapons in wars
• acute (immediate) poisoning when in contact
• destroy enzymes essential in nervous system functioning (resembles alkaloid poison muscarine found in fly amanita, a type of poisonous mushroom)

[Acetylcholine is an enzyme that transmits nerve impulse and will be destroyed as soon as impulse is sent. Cholinesterase is another enzyme which is responsible in disintegrate acetylcholine. Parathion destroys cholinesterase, causing accumulation of acetylcholine]

• causes uncoordinated movements (tremors, muscular spasms, convulsions)
• decomposes quickly (but long enough to be a threat)

- in Florida, two children had contact with an empty bag contaminated with parathion died while three of their playmates got ill

- in Wisconsin, one child who ran into the barn when the spraying was carried out and touched the nozzle died, same thing happened to another child who was playing at the adjoining field

- honey bees showed aggressive behaviors and performed frantic cleaning movement, died in half an hour

- a chemist with antidotes at hand swallowed 0.00424 ounce and got paralysis instantaneously

- used for suicide in Finland

- in California, there were more than 200 cases of accidental parathion poisoning per year

- in 1958, there were 100 cases in India and 67 cases in Syria

- in Japan, there were 336 cases per year

- in Riverside, California, 11 out of 30 orange pickers suffered retching, half-blind and semi-conscious for 16 to 19 days although the orchard was sprayed two and a half weeks ago

- even though parathion was applied 6 months ago with standard dosage, it was still found in orange peel

Malathion

• almost as familiar to public as DDT
• considered as the least toxic of this group of chemical
• it is safe due to detoxification in mammalian liver
• when combined with certain other organic phosphates (need not to be insecticide), poisoning effect will be up to 50 times than predicted

[The process is called potentiation as one compound destroys the detoxifying enzymes in liver, so the person will be vulnerable towards malathion. The two compounds do not have to be given at the same time to have that effect]

•  parathion and malathion are proven to magnify the toxicity of some drugs used as muscle relaxants and increase the sleeping time of barbiturates

- being used on nearly a million acres of Florida communities for the Mediterranean fruit fly

SYSTEMATIC INSECTICIDES

• spread through all the tissues of a plant or animal to make them toxic to pest
• found naturally or synthetically produced, most drawn from organophosphorus groups because the residue problem is less acute
• applied to seeds by soaking or coating combined with carbon
• the following plant generation produced might be poisonous as well
• in animals, the amount of chemical used must be in balance so that it could create an insecticidal effect in blood and tissues without causing poisoning 

- wheat growing in soil containing sodium selenate is immune from aphids or spider mites attack (the first systemic pesticide)

- in San Joaquin Valley, California, in 1959, 25 farm laborers suddenly fell ill after handling the bags of treated cotton seeds

- poisonous nectar was produced in areas treated with schradan before the flowers were formed

- used to control cattle grub (parasites to livestock)

Spraying of herbicides.
(Image taken from yardcare.com)

HERBICIDES - both organic or inorganic

Arsenic [as stated above]

Dinitrophenol

• strong metabolic stimulant
• once used as reducing drug but several patients died or suffered permanent injury, so its use as drug was stopped

Pentachlorophenol

• used as weed killer and insecticide along rail road tracks and waste areas
• fatally interfere with the body's source of energy

- a tank truck driver contacted the chemical with bare hand while preparing a cotton defoliant became acutely ill and died the next day although he washed his hands

Aminotriazole / Amitrol

• having relatively low toxicity
• can cause malignant tumors of thyroid for long exposure

Further readings:
United States Environmental Protection Agency website - Pesticides
United States Environmental Protection Agency website - Herbicides
Quebec website - Pesticide

Silent Spring - Extracted Information (The Obligation to Endure)

[Disclaimer: The informations below are taken from the book 'Silent Spring' written by Rachel Carson with some online researches. If there is any misleading information please let me know.]

(Image taken from the International Center for Autism Research and Education website)

Chapter 2: The Obligation to Endure

Man can hardly even recognise the devils of his own creation.   - Albert Schweitzer

1) After the emergence of life on Earth, physical forms and behaviours of living things are constantly manipulated by the environment so that both hostile and supporting elements can exist at the same time.

• Although there are radiation from natural rocks, cosmic rays, ultraviolet rays from the Sun and chemical leached from various minerals which might cause harm to living things in the environment however man-induced radiations and synthetic chemicals are way more dangerous because counterparts do not appear immediately and suddenly. 
• Pesticides, for example, are non-selective chemicals which are used to destroy pests. 
• As the so called pests develop resistance towards the particular chemical over generations, a more toxic one has to be engineered to counteract the resurgence of resistant pests. 

2) Despite the presence of insects pests, over production of food became a problem in America.

• Soil Bank Acreage Reserve Programme was launched in 1958 in order to reduce surplus crop production by limiting the acreage of basic crops of farmers and paying them. 
• In 1962, more than one billion dollars were paid by American taxpayers each year as total carrying cost of surplus food programme.

More information: Weessels Living History Farm

3) Cultivation of single crops facilitates insect infestation.

• This simplification will lead to an explosion of insect populations that depend on the specific plants to survive because there are more resources available. 

More information: 

Ryerson, K. A. (1933). History and significance of the foreign plant introduction work of the United States. Agricultural History, 7, 110-128.

(Image taken from the Secret of the Fed website)

4) Invasion of non-native insects species was mainly through importation of plants.

• There was no natural enemies existed in the new habitat.
• Almost half of the 180 or so major insect pests in the United States were introduced with nearly 200, 000 species of plants by the United States Office of Plant Introduction. 
• Ecologist Charles Elton pointed out that the invasion of new species from other places occurred naturally in a slow pace, but with assistance from human, it became a menacing threat. 

More information: 

Elton, C. S. (1958). The ecology of invasions by animals and plants. United States: Kluwer Academic Publisher B. V.

5) People were ignorant towards the nature of the threat.

• The manufacturers often claim that their products contain very low dosage of harmful substances that it won't cause any side effect in human health. 
• Truths are often covered up by the dominating industries to earn a fortune through people's limited awareness towards pesticides. 
• Carson did not contend to call for the banning of chemical insecticides but she wanted to let people know what they actually were facing.

Idealises life with only its head out of water, inches above the limits of toleration of the corruption of its own environment... Why should we tolerate a diet of weak poisons, a home in insipid surroundings, a circle of acquaintances who are not quite our enemies, the noise of motors with just enough relief to prevent insanity? Who would want to live in a world which is just not quite fatal?            - Paul Shepard

The obligation to endure gives us the right to know.                - Jean Rostand

Silent Spring - Review

The original edition of Silent Spring by Rachel Carson published in 1962.
(image taken from The Manhattan Rare Book Company website)

The term 'Silent Spring' literally means the season spring which is quiet, without the chirping of birds. Before I read this book, all I knew about it were it was written by Rachel Carson, a female scientist (a marine biologist to be exact, I found out about this later) in the era when men were dominant and it brought about a green revolution by getting the attention of the public about pesticide pollution.  So after I heard about this book a few times from my lecturers for the last two semesters, I thought I should read it at least once because it ignited the people's green awareness towards the environment at the time when there was no such thing as green movement.

Supported with a lot of scientific evidences from various research institutes and departments, Silent Spring has pointed out the dark side of pesticide usage despite of the 'convenience' claimed by the manufacturers and sellers. Pesticides including herbicides, insecticides and fungicides exist for only one purpose, to kill off so called 'pests'. At that time people did not realise how strong the poison was that almost all living organisms regardless of species were wiped out in a short period of time. Detailed data was embedded in the book stating the damages pesticides had given rise to towards the plants, insects, birds, fish and even human beings. At the beginning of the book, various types of pesticides were introduced, followed by their effects on living organisms and finally the carcinogenic impacts on human beings. The processes that initiated the effects were described scientifically in a simplified way that normal people would understand it. For those who studied biology, they will understand instantly about the processes which involve generation of energy in cells, inhibition of nerve functioning, carcinogenic agents etc.

The author, Rachel Carson who died of breast cancer two years after the publication of Silent Spring.
(image taken from The Pop History Dig website)

This book was not written to deny the usage of pesticide or to call for banning of pesticide but to acknowledge the people about what they were actually facing and to propose better alternatives to replace the unnecessary massacre of all living things directly or indirectly as the poison travelled and accumulated in body fat down the food chains. Biological control using the natural prey-predator and host-parasites relationships has been proved effective and cheap. If immediate treatment has to be done, direct applying of chemical at the affected spots will be better than vast spraying which contributes to the non-point source pollution when the air or water carries the chemicals to the other parts of our world. It is tragic when people had to pay for what they had not done, and not even known because the bitter truth was coated with sugar so that no one would question the true colour of pesticides.

Carson used simple language in delivering her concerns and scientific facts so that general public would understand what's going on in the perspective of science instead of stuffing the whole book with hard-to-digest scientific terminologies. Informations and knowledge are difficult to reach when they are just available in journals or reports which are accessible only by people in the academic and research fields who are only a small fraction out of the whole human population. The real danger often lies in people's ignorance when we don't even know what is threatening us. The efforts Carson made was a leap towards grassroot movement when people began to realise that the whole situation was being manipulated by certain parties for the political and economical benefits where human rights were not being taken care of.  

Bashfulgrass on the field.

P/S: It is quite enjoyable to read the Silent Spring because the words used are truly beautiful as if I am reading a literature full of knowledge. I will certainly read the whole book for the second time and extract the informations chapter by chapter. Although it might take some time, do read and digest it.