I was flabbergasted when I found out about this piece of New Zealand’s history. I don’t know what shocked me more: our government’s part in destroying an island and a people’s economy and way of life, or the fact that this history is so little known by New Zealanders.
New Zealand, along with Britain and Australia, gained the Pacific island of Nauru and its rich phosphate reserves as part of the spoils of the First World War. Over successive decades, these countries strip-mined most of the island for its phosphate, used to make fertiliser. This was a great boon for our agricultural industry (see also The “grasslands revolution”) , but Nauru paid a very high price.
About 80% of the island is now uninhabitable. This image shows the narrow habitable “green belt” surrounding the area mined for phosphate.
See also Nauru: Paradise well and truly lost
envirohistory NZ 
What about the cadmium (?) that was in the phosphate that came from there and was put everywhere. Apparently some farms in Waikato would have to have their land remediated if it were changed to residential – but as a farm it’s ok…
Yes, the story is shocking. The issue was probably better known about 30 or so years ago. In addition to what we have done to Nauru there is more to know. Over 60 years we were putting the phosphate on our farms (especially dairy) at a rate of about 2,000,000 tonnes annually. Phosphate from Nauru has a higher proportion of cadmium than the phosphate from other sources. As a result we were applying 30 to 40 tonnes of cadmium on our farms every year. Cadmium along with mercury, causes the most horrific human suffering which I myself have seen at close quarters in Japan. (Google “itai itai byo”). Cadmium is absorbed by root vegetables including potatoes and green vegetables as well as by rice as happened in Japan. We are “clean & green,” “100% pure”? Yeah right.
More info on the cadmium secret can be found at both the following:
http://www.3news.co.nz/The-dangers-of-Cadmium/tabid/367/articleID/293891/Default.aspx)
See also: An article by Kyra Xavia, Cadmium Concerns, in the July/August edition of Organic NZ