Director of Public Prosecutions Noordin Haji has filed a case at the High Court seeking to stop new tests for mercury on a consignment of fertiliser.
Under a certificate of urgency, the DPP challenged an order issued by a city magistrate court last week.
The court ordered Kenya Bureau of Standards to collect samples from Bollore Logistics warehouses today and test them on February 12.
Through senior prosecution counsel Alex Akula, the DPP said the matter is of great public interest.
According to an affidavit annexed to the court papers, the issue of the credibility arises because the fertiliser has been in the custody of Bollore, yet the samples were collected without the knowledge of the Directorate of Criminal Investigations.
The DPP added that he was never involved in the collection, testing or destruction of the samples collected by Kebs on January 24, 2018 and February 15, 2018.
But the company says when the samples were collected on June 19, 2018 by a multi-agency team, every member signed a document confirming the locking and sealing of the warehouse, which has been under 24-hour armed guard since.
The accused, including former Kebs MD Charles Ongwae, Mr Erick Kiptoo and OCP (K) Ltd, say they wonder why the DPP pressed charges against them three months after the tests were done and "allegedly" confirmed the presence of mercury in the fertiliser.
And contrary to claims that the accused were attempting to block the cause of justice, their lawyer said fresh tests, as correctly observed by the court, would uphold their right to a fair trial.
The magistrate court said the application by OCP (K) Ltd is valid.
The court said the fresh tests would assist in the case and ensure there is no miscarriage of justice.
The magistrate added that the tests would be conducted by Kebs in the presence of concerned parties.
In the application, OCP (K), a subsidiary of OCP-SA, a Moroccan fertiliser company accused the multi-agency team of conducting the tests in its absence.
The company through its lawyer Paul Muite said the consignment arrived in the country on January 23, 2018 but reports of mercury only surfaced in June.
Mr Ongwae and other State officials are accused of unlawfully releasing to OCP (K) Ltd 5,846,000 kilogrammes of compound fertiliser, which contained mercury.
The prosecution says they committed the offence between November 13, 2017 and June 7, 2018.
Other accused are inspection manager at Kilindini port Peter Kinyanjui, Coast regional manager Pole Mwangemi, port health officer Eric Kariuki, Mr Karim Lofti, Mr Benson Oduor, a supervisor with Bollore Transport and Logistics Kenya Ltd, Malika Karama and Younes Addou.
They deny attempted murder, abuse of office, commission of a felony and breach of trust charges.
The application opposing the tests will be heard Monday, February 11, 2019.