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# Units and proportions

A visualisation of the proportions between the same root units of measurement puts them into perspective.
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## Putting proportions into perspective

When we measure the presence of a compound in a sample, we usually work with concentrations, or proportions.

When using a specific unit (milligram), as long as we compare it to the same root unit (gram), the answer is a proportion and can be shown in % simply by multiplying by the relevant power of 10.

FOR EXAMPLE:
• 50 mg/g = 5%
• 50 g/kg = 5%
• 50 ml/l = 5%
• 50 mg/kg = 0.005%

However, for liquid samples, you sometimes want to know the presence of a compound in milligram (a unit of mass) per milliliter (a unit of volume) of the sample. This is not a simple proportion and requires that you know the density of the liquid. And unless the density is exactly 1g/ml, converting the result to a percentage is not merely as simple as decreasing by a factor of 10.

## Per cent

We’re all quite used to the concept of percentages, having been introduced to them at school level already. The literal meaning is “per hundred”.

EXAMPLE: 1% = 1 out of every 100

To put 1% in perspective, think of it as the bit of a joint you get when sharing it equally with 99 of your closest friends.

## Milligram per gram / part per thousand

In units of mass, a milligram per gram is the same as a part per thousand. The prefix “milli” refers to a thousandth.

EXAMPLE: 1 mg/g = 1 out of every 1 000

To put 1 mg/g in perspective, consider the portion of the width of a rugby field covered by the length of a 70mm joint.

## Milligram per kilogram / part per million

While “milli” refers to a thousandth, the prefix “kilo” refers to a thousand. A gram is a thousand times a milligram, and a kilogram is a thousand times a gram. This means a milligram per kilogram is a part per million

EXAMPLE: 1 mg/kg or 1 ppm = 1 out of every 1 000 000

It’s harder to perceive such a minute amount. Imagine the part of the NI between Cape Town and Johannesburg traversed by lining up twenty 70mm joints. That is roughly a part per million.

## Microgram per kilogram / part per billion

Going deeper, a microgram is a thousandth of a milligram, a millionth of a gram, and a billionth of a kilogram. This means a microgram per kilogram is a part per billion.

EXAMPLE: 1 µg/kg or 1 ppb = 1 out of every 1 000 000 000

A part per billion roughly equates to the length of five 70mm joints stacked on top of each other as a portion of the distance to the moon.

## The units you can expect in our certificates of analysis

 mg/g & % Potency & Cannabinoids, and Terpene Analysis mg/ml Potency & Cannabinoids, and Terpene Analysis on liquid samples where a Density Measurement was performed g/ml Density Measurement % Moisture Content and Total Ash cfu/g Microbial Count (colony forming units per gram) ppm Residual Solvents µg/kg (ppb) Heavy Metals mg/kg (ppm) Mycotoxins and Pesticides

Thank goodness for the metric system!

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### Pesticides we can test for

The standard multi-residue analysis includes testing for:

2-Phenylphenol
2,4′-DDE
2,4′-DDT
4,4′-DDE
4,4′-DDT
Abamectin B1a
Abamectin B1b
Acephate
Acetamiprid
Acetochlor
Acibenzolar-S-methyl
Acrinathrin
Aldicarb
Aldicarb sulfone
Aldicarb sulfoxide
Aldrin
Amitraz
Azinphos-ethyl
Azinphos-methyl
Azoxystrobin
BAC-C10
BAC-C12
BAC-C14
BAC-C16
BAC-C8
Benthiavalicarb isopropyl
Bifenthrin
Bitertanol
Boscalid
Bromophos-methyl
Bupirimate
Buprofezin
Captan
Carbaryl
Carbendazim
Carfentrazone-ethyl
Chinomethionate
Chlorantraniliprole
Chlordane
Chlorfenapyr
Chlorothalonil
Chlorpyrifos
Chlorthal-dimethyl
Clofentezine
Clothianidin
Coumaphos
Cyfluthrin
Cyhalothrin-lambda
Cymoxanil
Cypermethrin (sum of isomers)
Cyprodinil
DDAC-C10
DDAC-C8
Deltamethrin
Demeton-S-methyl
Demeton-S-methyl sulfone
Diazinon
Dichloran
Dichlorophene
Dichlorvos
Dieldrin
Difenoconazole
Diflubenzuron
Dimethoate
Dimethomorph
Diphenylamine
Dodine
Emamectin benzoate B1a
Emamectin benzoate B1b
Endosulfan-alpha
Endosulfan-beta
Esfenvalerate
Etaconazole
Ethofenprox
Ethoprophos
Etoxazole
Fenamidone
Fenamiphos
Fenarimol
Fenazaquin
Fenbuconazole
Fenbutatin oxide
Fenhexamid
Fenoxycarb
Fenpropathrin
Fenpyroximate
Fenthion
Fenvalerate
Flufenoxuron
Flumioxazin
Fluopicolide
Fluopyram
Flusilazole
Flutriafol
Folpet
Forchlorfenuron
Formetanate (hydrochloride)
Fosthiazate
Hexaconazole
Imazalil
Imidacloprid
Indoxacarb
Iprodione
Iprodione (GC)
Iprovalicarb
Isazophos
Isofenphos
Kresoxim-methyl
Lufenuron
Malathion
Mandipropamid
Metalaxyl-M
Methamidophos
Methidathion
Methiocarb
Methomyl
Methoxyfenozide
Metrafenone
Mevinphos-cis
Mevinphos-trans
Monocrotophos
Myclobutanil
Omethoate
Oxamyl
Oxydemeton-methyl
Oxyfluorfen
Paclobutrazol
Parathion
Parathion-methyl
Penconazole
Permethrin (sum of isomers)
Phenthoate
Phosmet
Piperonyl butoxide
Pirimicarb
Prochloraz
Procymidone
Profenofos
Propamocarb
Propargite
Propiconazole
Propoxur
Propyzamide
Proquinazid
Prothiofos
Pymetrozin
Pyraclostrobin
Pyrimethanil
Pyrimethanil (GC)
Pyriproxyfen
Quinoxyfen
Simazine
Spinetoram
Spirodiclofen
Spirotetramat
Spiroxamine
Sulfoxaflor
Tau-fluvalinate
Tau-fluvalinate
Tebuconazole
Temephos
Terbufos
Tetraconazole
Thiabendazole
Thiacloprid
Thiamethoxam
Thidiazuron
Thiophanate-methyl