health & science

Fossil-dirt nutrition claims under doubt

Can eating dirt made from fossils make animals grow bigger? It’s the claim made by the company planning to mine a geologically unique former crater lake in Middlemarch. Livestock health scientists are sceptical.

Animal nutrition specialists are questioning the claim Foulden Maar's fossil-rich diatomite, planned to be used as an additive in pig, chicken and turkey food, will grow bigger animals.

One said he laughed after reading Plaman Resource's website and thought the product was unlikely to be of interest to large industrial farmers.

Black Pearl, the trademarked name of the proposed product, has been described in company documentation as increasing average body weight gain and improving carcass yield and meat quality.

These claims are not made on its website, which only says: “Black Pearl offers nutritional benefits for livestock.”

The website says Foulden Maar’s black diatomaceous earth is “rich in natural organic matter (which contains humics, such as humic and fulvic acid) and other valuable nutrients, which have been shown to be beneficial in animal nutrition”.

Plaman Resources plans to mine 31 million tonnes from the Foulden Maar site and says the mine will employ 100 people over its projected 27-year lifespan.

The mining will destroy a geologically unique site full of fossils from 23 million years ago.

According to information in a report written by Goldman Sachs and leaked to the Otago Daily Times, the company expects revenue in 2022 to be $216 million, and by 2025 when production increases to 500,000 tonnes per year, a little over $1 billion.

It’s reported 13 countries have committed to trial Black Pearl. Countries listed as targets include Indonesia, Vietnam and Thailand.

The leaked report says: "Plaman controls the world's only known commercially viable supply of Black Pearl, and therefore its pricing can be maintained - and potentially increased - over the long term."

A former owner of the land has said the diatomite was of low quality. A subsequent owner went into liquidation, it estimated the reserves of diatomite to be five to six million tonnes and of too low a quality for many markets.

Local Dunedin South MP Clare Curran told Newsroom she had been “briefed by the company” and told it was a high value product.

She described the proposal Plaman Resources shared with her as a “significant green mineral project”. The company website includes a section called 'Sustainability' which lists food security, improved nutrition and environmental sustainability.

The diatomite, once mined from the open pit, would be transported by trucks to be dried and processed.

Estimations are at peak production 216 trucks per day will carry the diatomite from the mine site to the plant likely based in Milton, 100 kilometres away. It’s not known whether coal or gas would be used to dry it.

Once processed it would be sold as a food additive for commercial farming.

Curran said she thought claims made in news articles that the diatomite at Foulden Maar was low quality were misinformation.

“The applicants [Plaman Resources] have undertaken significant amount of research on it being produced as a natural growth stimulant for livestock. That's mainly poultry and, swine or pigs or whatever you want to call that industry, as an alternative to antibiotics.”

She said she could not share anything further, citing commercial sensitivity.

Good luck with that

Lincoln University’s Jim Gibbs lectures in livestock health and production, specialising in nutrition. He’s sceptical about claim made in 2018 media reports about trials of the product where Plaman Resources said trials showed “outstanding” results which were “off the charts”. No data was included in the article.

“If it was real, it would be published,” said Gibbs.

There are no published scientific articles with the results from Plaman Resources trials.

Gibbs explained the only difference between Black Pearl and diatomaceous earth currently available is the claims it contains humic and fulvic acid.

“These acids are present wherever you have organic matter being altered. In different soils you are going to have those organic matters they talk about. There’s no animal use in those organic matters, they don’t present an effective energy source. They’re not special, they don’t have any specific function.”

He said the diatomaceous earth was likely to have some trace elements, and the organic matter would increase the trace elements slightly.

“By in large it’s just a mineral supplement. It’s no magic anything. It's just a pretty straightforward, low-key, rather expensive way to supply a feed binder and some minerals.”

Another claim he sees made about diatomaceous earth is that it’s effective against parasites.

“They say it’s scratchy, and it scratches the outside of the parasites. When you read stuff like that, run for the hills - just run - run as fast as you can.”

He said the claim had been tested by a number of groups and the tests had failed. What is often seen though is a slight increase in animal weight. He suggested this could be due to the trace elements. In mineral-deficient areas even small amounts can make a difference. He suggested sometimes trials might not have rigorously accounted for the impact of increasing the trace elements the animals were receiving.

From the little Gibbs could see on the website he thinks it’s unlikely it will be an export success.

“Good luck to them with that one. If they're going to take it and transport it overseas, they'd want to have some pretty strong evidence that there was a particular benefit. From a chemical assessment perspective, there's none.”

Newsroom talked to two other New Zealand scientists about the claims on Plaman's website. Lincoln University soil scientist Amanda Black said she would want to read peer-reviewed papers with published results from clinical trials demonstrating Black Pearl's role in improved animal nutrition. Another Massey University scientist told Newsroom he couldn't comment, because there was no published evidence for him to read. 

Doubts abroad

It’s not just New Zealand scientists who have doubts about the product. North Carolina State University adjunct professor and poultry expert Simon Shane expressed concern in 2018 at the product claims.

“After 50 years as poultry veterinarian and doctoral level nutritionist, the claims presented and the nature of the product aroused my concern and hence the commentary.”

He questioned the absence of data from the trials of chickens and pigs which Plaman Resources claimed had “outstanding” results in a blog post.

“There is no published data in the peer-reviewed literature to support a claim that diatomaceous earth can serve as a growth promoter or enhance feed conversion efficiency in monogastric animals.”

He hoped Goldman Sachs, which lent Plaman Resources $30 million, based its investment on rigorous data.

“We are now functioning in a post-Theranos period and a conservative approach to investment in start-ups with unsubstantiated claims is injudicious ... Why diatomaceous earth taken from the ground in Otago, New Zealand should have growth promoting properties has yet to be explained.”

University students search for fossils at Foulden Maar. Photo:  Larusnz CC BY-SA 4.0

Food additive or palm oil plantation additive?

Initially Plaman Resource’s plan was to sell the diatomaceous earth mined from Foulden Maar as an additive for palm oil plantation fertiliser.

The Malaysian majority shareholder said this made sense as Malaysia had five million hectares of palm oil plantations. It said diatomite improved oil palms' resistance to a fungus-related disease.

In recent years, mention of this plan was abandoned, however, trademark applications from 2017 and 2018 in New Zealand and the United States show Plaman Resources has attempted to trademark Black Pearl as an animal food additive and a fertiliser. 

The leaked report talks about removing the Malaysian shareholder:

"The removal of Iris Corporation Berhad as a shareholder of Plaman Global as a key part of the corporate reorganisation will be viewed positively by the [New Zealand] ministers, since it removes any link between the Foulden Hills project and the potential use of Black Pearl as a fertiliser for palm oil plantations, which has been identified as a sensitivity for the local community."

The report said former Labour MP Clayton Cosgrove has been appointed by the company to lobby Labour ministers and gain approval for an application to purchase additional land.

Plaman resources are currently awaiting the outcome of a Overseas Investment Office application to purchase a second neighbouring piece of land to the mine site. This larger area would make the operation viable. Public submissions to the application can be made until a decision is announced.

Read more:

Who is the fossil mining company?

Opposition grows to fossil mining project

Dunedin's 'Pompeii' to be mined to make pig food

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