diff --git a/src/sofa/vtk/PolyDataVTKLoader.cpp b/src/sofa/vtk/PolyDataVTKLoader.cpp
index 5a72711..606e2d5 100644
--- a/src/sofa/vtk/PolyDataVTKLoader.cpp
+++ b/src/sofa/vtk/PolyDataVTKLoader.cpp
@@ -38,7 +38,7 @@ vtkSmartPointer<vtkDataSet> PolyDataVTKLoader::getDataSet(
 {
     const std::string extension = sofa::helper::downcaseString(fileName.getExtension());
 
-    static const std::unordered_map<std::string, std::function<vtkSmartPointer<vtkPolyData>()>> readers {
+    const std::unordered_map<std::string, std::function<vtkSmartPointer<vtkPolyData>()>> readers {
         {"ply", [&fileName](){return getPolyData<vtkPLYReader>(fileName);}},
         {"vtp", [&fileName](){return getPolyData<vtkXMLPolyDataReader>(fileName);}},
         {"obj", [&fileName](){return getPolyData<vtkOBJReader>(fileName);}},
diff --git a/src/sofa/vtk/UnstructuredGridVTKLoader.cpp b/src/sofa/vtk/UnstructuredGridVTKLoader.cpp
index 14abe8e..3c0c5bc 100644
--- a/src/sofa/vtk/UnstructuredGridVTKLoader.cpp
+++ b/src/sofa/vtk/UnstructuredGridVTKLoader.cpp
@@ -36,7 +36,7 @@ vtkSmartPointer<vtkDataSet> UnstructuredGridVTKLoader::getDataSet(
 {
     const std::string extension = sofa::helper::downcaseString(fileName.getExtension());
 
-    static const std::unordered_map<std::string, std::function<vtkSmartPointer<vtkUnstructuredGrid>()>> readers {
+    const std::unordered_map<std::string, std::function<vtkSmartPointer<vtkUnstructuredGrid>()>> readers {
         {"vtu", [&fileName](){return getUnstructuredGrid<vtkXMLUnstructuredGridReader>(fileName);}},
         {"vtk", [&fileName](){return getUnstructuredGrid<vtkUnstructuredGridReader>(fileName);}}
     };