How to Get the Heavy Metal Out of the Soil for Analysis - BCR Sequential Extraction

Some time ago I have shared information about heavy metal analysis (simple introduction & more detailed one). Basically the samples we use for those machines are in liquid form so that they can be vaporised followed by being atomised or ionised, then the machines will do the rest. How about solid sample such as soil? Sometimes spillage happens or maybe the natural content of heavy metal in the soil is much higher that it can be harmful to human health. There are a few digestion methods (yes it is called digestion, like how we digest the food to obtain the nutrients) can be used, and this one, this 3-stage BCR sequential extraction method is one of the most basic ones.

(photo taken from Bonnie Plant website)

To make it simple, the same soil will go through 3 times of digestions using different solvent respectively to target heavy metals in different forms for several hours on a shaker to mix well(or overnight, depending on the stage), then it will be centrifuged (spun with high speed to separate the soil from the solvent) so that we can obtain the solvent which will be analysed later on. After we are done with each stage, the soil will be 'washed' with distilled water before the following stage can be carried out to remove the solvent in previous stage to avoid contamination (but remember not to loss any of the soil during the process!). Even though we have carried out the 3 stages of digestion, there still will be some residual heavy metal that is bound to the soil and is not removable with the above methods. Since they are tightly bound, we can ignore them as they can't really move around in the soil and will not bring much impact to us. For this whole process, only 1 gram of oven-dried soil is needed!

Atomic Absorption Spectrometry (AAS) and Inductively Coupled Plasma - Mass Spectrometry (ICP-MS)

When it comes to analytical chemistry for inorganic elements especially metals, it is almost impossible to not include Atomic Absorption Spectrometry (AAS) and Inductively Coupled Plasma - Mass Spectrometry (ICP-MS). Compared to simpler laboratory analysis that we have done during matriculation and first year such as titration or measurement using portable meter, the usage of AAS and ICP-MS is rather complex in terms of the whole mechanism used within the instrument. However, we can precisely know the concentration of element contained by the sample using these two methods with the careful preparation of standard solutions. I have written a similar post regarding heavy metal analysis technology last year, but this time we are going to look into the details to understand better how they work behind the shell of the machines.

(Image taken from the website of Avomeen Analytical Services.

Heavy Metal Analysis Technology - AAS & ICP-MS

I believe that most people know about the sinister side of heavy metals. Here are a few examples:

• Mercury poisoning - the emergence of Minamata disease in Japan
• Lead poisoning - a decades old problem 
• Cadmium poisoning - the Itai-itai disease in Japan
• Arsenic poisoning - the once-popular homicide 
• Silver poisoning - the Argyria disease

Compared to Emerging Contaminants (ECs), heavy metal in water is not a new issue. Water filtration system today can easily remove heavy metal from the water. However, heavy metal contamination happens easily due to all kinds of industrial activities going on that discharge wastes loaded with heavy metals. Therefore, the monitoring of water quality in terms of heavy metal contamination should be done from time to time.

The laboratory which is specific for Atomic Absorption Spectrometry (AAS).

Agricultural Expo and UPM 38th Convocation Festival - Environmental Forensic Booth

This was the first time I went to the Agricultural Expo and UPM 38th Convocation Festival held at Bukit Ekspo with the theme 'Agricultural Innovation Centre of Living'. It is an annual event which will be held during the convocation period with exhibitions by various faculties and departments of UPM. Me and Erika spent around two hours there to explore the contribution of UPM mainly in the agricultural sectors. Here's the photo blog of some of my findings there.

The exhibition bus by UPM Research Centre about city agriculture.

The inside of the exhibition bus. Products made of extract of plants are exhibited (these products are not commercialised yet). Information regarding the medical usage of traditional plants are being shown as well. The person in-charged there was very helpful in giving explanation about those plants. It's really eye-opening that actually plants that we might easily oversee bring health benefits.

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

The Cove - Review

(Image taken from the Examiner.com website)

This is the second documentary that I watched and decided to write a post about it. In my the other blog I wrote a post regarding extracted information from the documentary The Inconvenient Truth, the facts behind global warming. When I am trying to do the same to The Cove, I found difficulties in doing so because The Cove is more like a real life action movie of a group of activists risking their life to reveal the truth behind dolphin hunting in Taiji, Japan rather than a collection of facts. This documentary was awarded the Oscar Academy Award for Best Documentary Feature in 2010 as they brought attention of the world towards inhumane treatment towards dolphins especially the dolphin slaughter in Taiji, Japan.

Beautiful cove of Taiji.
(Image taken from Tiffany&Ink blog)

We often see the dolphin shows on TV where the dolphins leap out of the water gracefully and interact cheerfully with their trainers. This dolphin show trend was not popular until the release of Flipper TV Series in 1964 which was about story of a bottlenose dolphin named Flipper and Ricks family. Since then, dolphin captivity became more common and makes a lot of money from the audiences. However, people do not know the suffering of dolphins behind the show just like other animals in the circus. Ok this might not be the focus of the documentary but the dolphin slaughter which is covered up by the Japan government. Yes we slaughter cows, pigs, poultries, fish etc. for food but the secret slaughter of dolphins is just so unreasonable since their meat is not suitable to be consumed and they have high intelligence, even higher than dogs and cats (many people around the world are mad at dog meat trade in China). There is no big protest towards dolphin slaughter in Japan because people do not know about the blood spilled at the cove in Taiji.

Pristine sea stained red with blood.
(Image taken from Digital Journal website)

During the seasonal migration of dolphins passes by Japan in September, that is when the hunting season for dolphins begins. The hunters scare the dolphins to the shore by creating noise and trap them there until the next day when the dolphin trainers will come and select the ones they want. The rest of the dolphins will end up bleeding to death at the cove, out of everyone's sight. The number of death can be up to 23 000 each year. It was a very risky and tough work of the team leading by Louie Psihoyos in uncovered what has been happening behind the beautiful cove of Taiji by using hidden cameras and hydrophones. My heart was in my mouth when they were carrying out the mission in the dark because if they were caught, they would be dead. The team also did surveys on the streets and found that hunting dolphins as the Japanese culture was just a lie to make things seem rightful. The consumers in Japan are even tricked to buy dolphin meat which is sold as high quality whale meat. If you watch the documentary you can see things done by the Japan government to hide away the ugly side of Taiji.

Dolphin meat? Whale meat?
(Image taken from National Geographic website)

I do not hate Japan because of things they have done in the past and the dolphin slaughter, but the lies they have told to the world make me feel disgusted towards the Japan government. Since animals are given to human as food, slaughtering of animals is normal but unnecessary killing is just a sin that is unforgivable (of course when people see the scenes in the normal slaughter house they will be disgusted as well). They kill because they can.

Here are some dolphins facts extracted from the documentary:

• In the wild, dolphins can travel 40 miles per day.
• Instead of sight, sonar system is dolphins' main sense in 'seeing'.
• Due to their sensitivity towards sound, dolphins get stressed up when the surrounding is too noisy.
• The language people used to communicate with dolphins is a version of American sign language.
• Breathing is a voluntary movement for dolphins (unlike human, we breath automatically) which requires conscious effort. 
• Dolphins are self-aware, they can understand how to manipulate circumstances, how to interact with people and how to use their imagination in creating innovatively.
• During the Greek era, harming a dolphin could lead to death sentence as dolphins were known to save humans' lives.
• Two animal rights activists, Jenny May and Jane Tipson got murdered because they tried to stop dolphin traffics.
• Dolphin meat is heavily loaded with mercury (20 times higher than recommendation by World Health Organisation), a heavy metal which contributes to Minamata disease. 

Atlantic Bottlenose dolphins. Bottlenose dolphin is the one common in dolphin shows.
(Image taken from Horizon International Solutions site)

Take your time and watch the movie. Brace yourself for some unpleasant feelings. For your information, the effort of old Ric to rescue the dolphins is still going on. You can check out this website to find out more.