natural or man-made chemicals? adapted from a presentation by penny le couteur, the fraser...

Natural or Man-made Chemicals?

Adapted from a presentation by Penny Le Couteur,

The Fraser Institute, Vancouver, Canada

“All substances are poisonous,there is none which is not a poison; the right dose differentiates a poison from a remedy.”

Paracelsus circa 1538

The great myth

“Natural is good;

man-made is bad”

It may be natural but you’ll be just as dead!

The seven most deadly chemical compounds

LD50 /mg/kg

Botulinum toxin A 3 x 10-8

Tetanus toxin A 5 x 10-6

Diphtheria toxin 3 x 10-4

Dioxin * 3 x 10-2

Muscarine 2 x 10-1

Bufotoxin 4 x 10-1

Sarin * 4 x 10-1

LD50 = The lethal dose of a compound for 50% of animals exposed

* Synthetic

The best chemists can do

O

O Cl

Cl

Cl

Cl

(Dioxin)

2,3,7,8-tetrachlorodibenzo-p-dioxin

Viktor YushchenkoPresident of the Ukraine

July 2004 December 2004

Muscarine - from mushrooms

OCH2

H3C

HO

N

CH3

CH3

CH3

Cl

Bufotoxin – from the common toad

O

CH3

OH

O

CH3

O C

O

CH3

O

C

(CH2)6O C

O

NH CH

COOH

CH2 CH2 CH2 NH C

NH

NH2

The next ten …. (most deadly)

* Synthetic

LD50/ mg/kg

Strychine 5 x 10-1

Soman * 6 x 10-1

Tabun * 6 x 10-1

Tubocurarine chloride 7 x 10-1

Rotenone 3

Isoflurophate * 4

Parathion * 4

Aflatoxin B1 10

Sodium cyanide * 15

Solanine 42

Vitamin C

O O

OHHO

CH

CH2OH

HO

Ascorbic acid

Other variations of “natural is good; man-made is bad”

• Synthetic chemicals were not around as man evolved so we haven’t had time to become

resistant to them as we have to naturally occurring compounds.

• Synthetic chemicals bioaccumulate in our bodies.

Chemicals in food: Advertisements from “organic food”

stores

“We read the labels so you don’t have to. We want you to concentrate on how good the food tastes and not worry about words that you can’t

pronounce”

Chemicals in food: Advertisements from “organic

food” stores

“We keep the chemicals out of your food”

Chemicals in food: Advertisements from “organic

food” stores

“We think your food tastes better

without the flavour of preservatives”

Chemicals used to preserve food

Chemical Use

Ascorbic acid Antioxidant/antimicrobial

BHA Antioxidant

Calcium propionate Mold inhibitor

EDTA Antioxidant

Sodium benzoate Microbial inhibitor

BHT Antioxidant

Sodium nitrite Microbial inhibitor in meat

Sorbic acid Mold inhibitor in cheese

BHA= butylated hydroxyanisole BHT = butylated hydroxytoluene EDTA = ethylenediaminetetraacetic acid

Sodium nitrite

Risk: Cancer from nitrosaminesBenefit: Prevents botulism in meats

NO2- + HCl HNO2

+ Cl-

HNO2 + (CH3)2NH (CH3)2NNO + H2O

Natural toxins in food

Chemical Food source Hazard

Allyl isothiocyanate Brown mustard, horseradish, garlic

Tumours

Benzo(α)pyrene BBQ/smoked meats Stomach cancers

Cyanides Bitter almonds, cashews, lima beans

General toxicity

Nitrosoamines Cooked bacon Cancer

Estragole Basil, fennel, tarragon

Tumours

Glycyrrhizic acid Liquorice Hypertension/heart

Hydrazines Raw mushrooms Cancer

Natural toxins in food –part 2

Chemical Food source Hazard

Myristicin Nutmeg, parsley, dill, carrots, celery, pepper

Hallucinations/liver damage/death

Oxalic acid Rhubarb, spinach Kidney damage/death

Saxitoxin Shellfish Paralysis/death

Symphatine Comfrey plant Tumours

Tannins & tannic acid

Black tea, coffee, cocoa Cancers/ throat & mouth

Tetrodotoxin Puffer fish Paralysis/death

Don’t worry, it’s organic•Organic farming is a multi-dollar industry that relies on the public’s perception that organic food is more healthy.

•There is little evidence to suggest that organic fruit and vegetables are any healthier than conventional produce.

•Some forms of organic farming may introduce natural toxins into consumers’ food.

Chemistry World, June 2004

Science writer John Emsley quotes

• We come into this world with a wonderful built-in detoxifying system that protects us against thousands of natural toxins every day.

• Cancer (from synthetic chemicals) is a risk, but the risk may be so low as to be worth ignoring.

Cosmetics•Cinnamon•Citrus•Angelica•Almond extract•Clove•Bergamot •Cornstarch•Fennel•Geranium•Lavender•Lemon balm•Lime•Papaya•Peppermint•Rose•Thyme•Witch hazel•Wintergreen

Should DDT be banned everywhere?

CH

CCl3

ClCl