Esther Mahlangu, a contemporary South African artist, has her thumb ink-marked before casting her vote at KwaMhlanga, Mpumalanga. Picture: Themba Hadebe/AP

Cape Town – With the Independent Electoral Commission (IEC) investigating the failure of the "indelible" ink used to mark voters' thumbs, enabling illegal double voting, perhaps microchips could be a safer bet in future.

This is of course if South Africans are willing – or could afford – having microchips implanted. About 3 000 Swedes have had a single microchip inserted under their skin, which is as tiny as a grain of rice, so that they would have no need to carry IDs and daily necessities such as key cards and train tickets, Agence France-Presse reported.

The IEC says it will be seeking answers from its supplier about what could have gone wrong with the so-called "indelible" ink pens used in Wednesday's election. 

Tender documents show that the IEC awarded a tender worth R2.7 million for the supply of the pens in February last year, Business Insider SA reported.

The supply contract went to Lithotech Exports, a division of the JSE-listed Bidvest, which beat out six other security-product and printing companies.

The ink used to mark the left thumb of every voter is supposed to remain visible for at least seven days and not meant to be easy to remove. This has led to political parties lodging official concerns about the double-voting they believe may have resulted.

Experts and tender documents suggest there are multiple ways indelible ink can fail, especially if you skimp on the silver nitrate. It's believed a stockpile of 165 000 pens were needed, suggesting a per unit price of just more than R16 a pen, a price that raised eyebrows among experts as low.

According to Justin Howard, of specialist voting ink manufacturer AP Africa, which has previously supplied the IEC but was not involved in the current contract, voting ink pens can fail because of mechanical problems with the pen itself or because the ink is not properly applied, or even if voters' fingers are oily enough. 

As for micro chips, the state-owned SJ rail line in Sweden started scanning the hands of passengers with biometric chips to collect their train fare while on board. 

Inserting the microchip is similar to that of a piercing and involves a syringe injecting the chip into the person's hand. However, the chip implants could cause infections or reactions in the body's immune system, Ben Libberton, a microbiologist at MAX IV Laboratory in southern Sweden, told AFP.

About four years ago, Swedish biohacking group Bionyfiken started organising "implant parties" – where groups of people insert chips into their hands en masse – in countries including the US, UK, France, Germany and Mexico.