The tests were carried out by Hill Laboratories, which is accredited by International Accreditation New Zealand (IANZ).
Dr Nick Kim, from Massey University's school of public health, interpreted the findings for the Herald.
He said the sample contains the same free chlorine (hypochlorite) content as a 3 per cent solution of household bleach like Janola.
"This is relatively dilute in comparison to concentrated bleach solutions, but would be effective as a surface disinfectant.
"What you are doing is killing off the microbes and bugs on the bench and if you drink it you are killing off the natural microbes in your gut, gastrointestinal tract and your stomach which you rely on for digestion."
Kim noted that New Zealand drinking water standards did not apply to commercial products like Te Kiri Gold, but said they could serve as a "useful point of reference".
"The measured content of free chlorine in the sample is 220 times higher than the limit we would apply to New Zealand drinking water."
On being told the results and Kim's analysis, Coxhead said the chlorine used in Te Kiri Gold (hypochlorous acid) differed to the free chlorine tested in the laboratory.
Kim replied: "It doesn't matter what you call it, it's the same thing and the level was still high."
He also commented on the high amount of salt in the solution.
The Australian and New Zealand governments recommend adults eat less than 6g of salt a day. Drinking 600ml of Te Kiri Gold a day, the recommended dose, would be equivalent to about 9g of table salt, one-and-a-half times the recommended limit, without dietary salt added.
The eight-week programme costs $1600. After eight weeks users would digest half a kilo of salt, which could be harmful to kidneys, heart and blood pressure.
Coxhead conceded he was trying to reduce the amount of sodium in his "latest batch".
"I think if you test a bottle now it would be less, but at the same time I have to have the hypochlorous acid do its job. It's very tricky.
"I am not a scientist or a doctor and it worries me that if I change something it may no longer work and I need to give it to people who need it now.
"So the salt might be high for a short period of time but dying of cancer isn't too flash either."
Kim said: "If I had cancer I wouldn't take this product. I can't see any health benefit from swallowing solution with diluted bleach and a high concentration of salt."
Sir Colin was contacted by Coxhead after going public with his cancer battle last August. Coxhead told the Herald soon after: "I knew I could help him. It broke my heart to see him like that - he is such a great Kiwi."
In that interview Coxhead said Te Kiri Gold came from experiments on his farm that started three years ago.
"It's just made of salt water and electricity - there are not many ingredients in it but it's the way it's made."
Coxhead claimed it changed the molecular structure of the immune system so the water could penetrate to the bone, then to the cancer cells.
A list of instructions that comes with postal orders says the water starts killing cancer cells as soon as you ingest it and patients will "feel better" for the first days.
But there was a warning that symptoms could worsen between day three and week four.
"We believe this is caused by the breakdown of cancer cells and the body's need to process and excrete toxins being released," the instructions say.
Kim said that if hypochlorite got into the bloodstream it could kill cells but relatively indiscriminately - it would kill some cancer cells but could damage ordinary cells too.
Te Kiri Gold's website states: "Te Kiri Gold is an organic liquid, manufactured from the same ingredients and in a similar manner, to the way that your body creates your immune system components."
It also notes: "Any claims of improvement in well-being, tumor [sic] reduction or cancer remission on this site are made by people whom have taken TKG and not by staff or shareholders of Te Kiri Gold."
Coxhead said generally speaking his clients were "terminal and had been through the cancer treatment process".
"A lady who had cervical cancer drank the water and was clear in 10 days. Another man with a melanoma on the top of his head was so bad you could see his skull. After drinking TKG for three weeks he came back, took his hat off - it was gone," he said.
The product's website has published three testimonials from other cancer patients.
The website does not say whether the patients who provided testimonials were having medical treatment for the disease as well.
Kim noted that analytical chemistry measurements were not capable of detecting any "mystical properties that the solution might be held to possess, such as ability to alter the quantum structure of the water".
He also called for an operational government agency to assess such products. "If there are products on the market with potential health claims made about them - this agency could check them on the public's behalf."
The Ministry of Health said Te Kiri had not been through a clinical trial, nor did it have an application for a trial, and was not deemed safe by Medsafe.
It said if a product made therapeutic claims, such as relief of symptoms, it was regulated under the Medicines Act 1981, administered by the Ministry of Health.
The Act says any medicine must undergo a rigorous assessment plus gain approval for use before they can be generally supplied and advertised in New Zealand.
That assessment process is operated by Medsafe, on behalf of the Minister of Health, and ensures that medicines meet international requirements for quality, safety and efficacy.
Dr Chris Jackson, the Medical Director of the Cancer Society, said because Te Kiri Gold was not a licensed product the society would not recommend it.
"Any organisation selling a medical treatment that claims to cure cancer, before they have been through clinical trials to test and prove safety and effectiveness, is misleading and potentially dangerous," he said.
The Cancer Society relied on research and evidence where drugs or other 'cures' for cancer should be evaluated according to robust systems like the ESMO Magnitude of Clinical Benefit scale.
"We would only recommend a medical treatment once it has been through clinical trials and approved by Medsafe."
He said if anyone was considering an alternative treatment option, the Cancer Society would suggest they seek advice from their oncologist or medical practitioner.
Consumer New Zealand said all companies had a legal obligation to ensure products they sold were safe.
The Fair Trading Act also prohibited traders from making unsubstantiated claims, with companies that misled consumers about a product's benefits facing fines of up to $600,000.