Effects of ammonium fluoride on the decomposition of geochemical samples as fluorinating agent and its analytical application.
In this work, the effects of ammonium fluoride on the decomposition of geochemical samples were investigated by analyzing some certified reference materials (CRM). The major and minor elements were detected by inductively coupled plasma optical emission spectrometry (ICP-OES), while trace and ultra-trace elements were analyzed by inductively coupled plasma mass spectrometry (ICP-MS). Decomposition time, temperature and the amount of ammonium fluoride were studied in detail. In the process of sample decomposition, on one hand, ammonium fluoride was used as the fluorinating agent because ammonium fluoride can be dissociated under acid medium to yield fluoride ions to attack silicon compound effectively. On the other hand, ammonium fluoride was used as a latent solvent since ammonium salt may dissolve insoluble fluorine compounds. The removal of insoluble fluorine compounds decreased the memory effect on digestion vessels caused by fluoride coprecipitation. By testing CRMs and many real samples, it was found that trace and ultra-trace elements could be digested using ammonium fluoride instead of hydrofluoric acid and the dissolution ratios of major and minor elements, for example Al, Ca, Mg, Fe, Na and K, improved noticeably. Moreover, the use of ammonium fluoride instead of hydrofluoric acid contributes to a greener environment and safer for operators.
Recommended Medical Treatment for Hydrofluoric Acid Exposure
This Booklet describes the special First Aid and Medical Treatment measures necessary following exposure to or injury from HYDROFLUORIC ACID. PREVENTION of exposure or injury must be the primary goal. Preventive measures include: 1. Making everyone who handles or uses HF aware of its properties and dangers. 2. Training everyone who uses HF in proper handling and safety precautions. 3. Utilizing all appropriate engineering controls, and making sure that the controls are maintained and functioning properly. 4. Requiring everyone who handles or uses HF to have available the proper safety and personal protective equipment, to be trained to use the equipment, and to always use the equipment when necessary. 5. Arranging ahead of time to provide first aid or medical treatment measures if necessary. NOTE: In addition to the usual medical history, the physician will find it helpful to obtain the following inform exposed/affected, first aid measures instituted (what, when, how long). Injuries due to dilute HF solutions or low
The efficacy of calcium gluconate in ocular hydrofluoric acid burns
1 Although calcium gluconate (CG) is recommended in the treatment of hydrofluoric acid (HF) eye burn its efficacy seems to be controversial, and controlled human or animal studies are limited. The study's objective is to compare the efficacy of 1% CG and normal saline irrigation for the treatment of HF eye injury in animals. 2 0.05 ml 2% HF was instilled to anesthetized rabbit's eyes. One minute later, four treatment groups were studies: (1) irrigation with normal saline followed by topical antibiotics, corticosteroids and cycloplegics for 48 h (n=10); (2) irrigation with 1% CG followed by the same topical treatment (n=9); (3) as group 1 and 1% CG drops over 48 h (n=10); (4) as group 3, and injection of 1% CG subconjunctivally after irrigation (n=9). 3 Corneal erosion area, corneal haziness, conjunctival status, vascularization (pannus) and acidity were assessed before injury, immediately after intitial treatment and 1, 2, 7 and 14 days thereafter by slit lamp aided by fluorescein staining. 4 Conjunctival pH dropped from 6.0 - 6.5 to 2.5 - 3 after injury and increased to 6 - 6.5 after irrigation. Corneal erosion: smaller in groups 2, 3, significantly so at 2 days, but not different at 14 days. Corneal haziness: more severe in group 4, at 14 days, insignificant. Conjunctival damage: significantly worse in group 4 at 2, 7 and 14 days. Pannus appeared in 2 - 4 eyes in each group. 5 It seems that for HF injury 1% CG did not have any significant advantage over saline irrigation and topical treatment only. It might have some initial and temporary effect on healing process especially that involving erosion. Given subconjunctivally, 1% CG may be toxic and worsens clinical outcome.